import java.io.IOException;
import java.io.InputStream;
import java.util.*;

public class Main {
    public static void main(String[] args){
        FastScanner sc = new FastScanner();
        int n = sc.nextInt();
        int[] rates = new int[n];
        long maxv = -2000000000;
        for(int i=0; i<n; i++){
            rates[i] = sc.nextInt();
        }
        /**
         * この場合,O(n^2)で n=200000 20^10　> 10^8   
         * for(int j=1; j<n; j++){
         *             for(int i=0; i<j; i++){
         *                 maxv = Math.max(rates[j] - rates[i], maxv);
         *             }
         *         }
         */
        
        // minvを保持することで　O(n)
        long minv = rates[0];
        for(int j=1; j<n; j++){
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        }


        System.out.println(maxv);

    }

    static class FastScanner {
        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;
        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }
        private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
        private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
        public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
        public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }
        public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }
        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        }
        public double nextDouble() { return Double.parseDouble(next());}
    }
} import java.io.IOException; IOException java.io import java.io.InputStream; InputStream java.io import java.util.*; util.* java public class Main {
    public static void main(String[] args){
        FastScanner sc = new FastScanner();
        int n = sc.nextInt();
        int[] rates = new int[n];
        long maxv = -2000000000;
        for(int i=0; i<n; i++){
            rates[i] = sc.nextInt();
        }
        /**
         * この場合,O(n^2)で n=200000 20^10　> 10^8   
         * for(int j=1; j<n; j++){
         *             for(int i=0; i<j; i++){
         *                 maxv = Math.max(rates[j] - rates[i], maxv);
         *             }
         *         }
         */
        
        // minvを保持することで　O(n)
        long minv = rates[0];
        for(int j=1; j<n; j++){
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        }


        System.out.println(maxv);

    }

    static class FastScanner {
        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;
        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }
        private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
        private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
        public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
        public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }
        public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }
        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        }
        public double nextDouble() { return Double.parseDouble(next());}
    }
} Main public static void main(String[] args){
        FastScanner sc = new FastScanner();
        int n = sc.nextInt();
        int[] rates = new int[n];
        long maxv = -2000000000;
        for(int i=0; i<n; i++){
            rates[i] = sc.nextInt();
        }
        /**
         * この場合,O(n^2)で n=200000 20^10　> 10^8   
         * for(int j=1; j<n; j++){
         *             for(int i=0; i<j; i++){
         *                 maxv = Math.max(rates[j] - rates[i], maxv);
         *             }
         *         }
         */
        
        // minvを保持することで　O(n)
        long minv = rates[0];
        for(int j=1; j<n; j++){
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        }


        System.out.println(maxv);

    } main {
        FastScanner sc = new FastScanner();
        int n = sc.nextInt();
        int[] rates = new int[n];
        long maxv = -2000000000;
        for(int i=0; i<n; i++){
            rates[i] = sc.nextInt();
        }
        /**
         * この場合,O(n^2)で n=200000 20^10　> 10^8   
         * for(int j=1; j<n; j++){
         *             for(int i=0; i<j; i++){
         *                 maxv = Math.max(rates[j] - rates[i], maxv);
         *             }
         *         }
         */
        
        // minvを保持することで　O(n)
        long minv = rates[0];
        for(int j=1; j<n; j++){
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        }


        System.out.println(maxv);

    } FastScanner sc = new FastScanner(); sc new FastScanner() int n = sc.nextInt(); n sc.nextInt() sc.nextInt sc int[] rates = new int[n]; rates new int[n] n long maxv = -2000000000; maxv -2000000000 2000000000 for(int i=0; i<n; i++){
            rates[i] = sc.nextInt();
        } int i=0; int i=0; i 0 i<n i n i++ i++ i {
            rates[i] = sc.nextInt();
        } {
            rates[i] = sc.nextInt();
        } rates[i] = sc.nextInt() rates[i] rates i sc.nextInt() sc.nextInt sc long minv = rates[0]; minv rates[0] rates 0 for(int j=1; j<n; j++){
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        } int j=1; int j=1; j 1 j<n j n j++ j++ j {
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        } {
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        } maxv = Math.max(maxv, rates[j] - minv) maxv Math.max(maxv, rates[j] - minv) Math.max Math maxv rates[j] - minv rates[j] rates j minv minv = Math.min(minv, rates[j]) minv Math.min(minv, rates[j]) Math.min Math minv rates[j] rates j System.out.println(maxv) System.out.println System.out System System.out maxv String[] args args static class FastScanner {
        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;
        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }
        private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
        private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
        public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
        public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }
        public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }
        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        }
        public double nextDouble() { return Double.parseDouble(next());}
    } FastScanner private final InputStream in = System.in; in System.in System System.in private final byte[] buffer = new byte[1024]; buffer new byte[1024] 1024 private int ptr = 0; ptr 0 private int buflen = 0; buflen 0 private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        } hasNextByte {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        } if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            } ptr < buflen ptr buflen {
                return true;
            } return true; true {
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            } ptr = 0 ptr 0 try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                } IOException e {
                    e.printStackTrace();
                } e.printStackTrace() e.printStackTrace e {
                    buflen = in.read(buffer);
                } buflen = in.read(buffer) buflen in.read(buffer) in.read in buffer if (buflen <= 0) {
                    return false;
                } buflen <= 0 buflen 0 {
                    return false;
                } return false; false return true; true private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;} readByte { if (hasNextByte()) return buffer[ptr++]; else return -1;} if (hasNextByte()) return buffer[ptr++]; else return -1; hasNextByte() hasNextByte return buffer[ptr++]; buffer[ptr++] buffer ptr++ ptr return -1; -1 1 private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;} isPrintableChar { return 33 <= c && c <= 126;} return 33 <= c && c <= 126; 33 <= c && c <= 126 33 <= c 33 c c <= 126 c 126 int c c public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();} hasNext { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();} while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; hasNextByte() && !isPrintableChar(buffer[ptr]) hasNextByte() hasNextByte !isPrintableChar(buffer[ptr]) isPrintableChar(buffer[ptr]) isPrintableChar buffer[ptr] buffer ptr ptr++ ptr return hasNextByte(); hasNextByte() hasNextByte public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        } next {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        } if (!hasNext()) throw new NoSuchElementException(); !hasNext() hasNext() hasNext throw new NoSuchElementException(); new NoSuchElementException() StringBuilder sb = new StringBuilder(); sb new StringBuilder() int b = readByte(); b readByte() readByte while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            } isPrintableChar(b) isPrintableChar b {
                sb.appendCodePoint(b);
                b = readByte();
            } sb.appendCodePoint(b) sb.appendCodePoint sb b b = readByte() b readByte() readByte return sb.toString(); sb.toString() sb.toString sb public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        } nextLong {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        } if (!hasNext()) throw new NoSuchElementException(); !hasNext() hasNext() hasNext throw new NoSuchElementException(); new NoSuchElementException() long n = 0; n 0 boolean minus = false; minus false int b = readByte(); b readByte() readByte if (b == '-') {
                minus = true;
                b = readByte();
            } b == '-' b '-' {
                minus = true;
                b = readByte();
            } minus = true minus true b = readByte() b readByte() readByte if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            } b < '0' || '9' < b b < '0' b '0' '9' < b '9' b {
                throw new NumberFormatException();
            } throw new NumberFormatException(); new NumberFormatException() while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            } true {
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            } if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                } '0' <= b && b <= '9' '0' <= b '0' b b <= '9' b '9' {
                    n *= 10;
                    n += b - '0';
                } n *= 10 n 10 n += b - '0' n b - '0' b '0' if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                } b == -1 || !isPrintableChar(b) b == -1 b -1 1 !isPrintableChar(b) isPrintableChar(b) isPrintableChar b {
                    return minus ? -n : n;
                } return minus ? -n : n; minus ? -n : n minus -n n n {
                    throw new NumberFormatException();
                } throw new NumberFormatException(); new NumberFormatException() b = readByte() b readByte() readByte public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        } nextInt {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        } long nl = nextLong(); nl nextLong() nextLong if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException(); nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE nl < Integer.MIN_VALUE nl Integer.MIN_VALUE Integer Integer.MIN_VALUE nl > Integer.MAX_VALUE nl Integer.MAX_VALUE Integer Integer.MAX_VALUE throw new NumberFormatException(); new NumberFormatException() return (int) nl; (int) nl public double nextDouble() { return Double.parseDouble(next());} nextDouble { return Double.parseDouble(next());} return Double.parseDouble(next()); Double.parseDouble(next()) Double.parseDouble Double next() next public class Main {
    public static void main(String[] args){
        FastScanner sc = new FastScanner();
        int n = sc.nextInt();
        int[] rates = new int[n];
        long maxv = -2000000000;
        for(int i=0; i<n; i++){
            rates[i] = sc.nextInt();
        }
        /**
         * この場合,O(n^2)で n=200000 20^10　> 10^8   
         * for(int j=1; j<n; j++){
         *             for(int i=0; i<j; i++){
         *                 maxv = Math.max(rates[j] - rates[i], maxv);
         *             }
         *         }
         */
        
        // minvを保持することで　O(n)
        long minv = rates[0];
        for(int j=1; j<n; j++){
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        }


        System.out.println(maxv);

    }

    static class FastScanner {
        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;
        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }
        private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
        private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
        public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
        public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }
        public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }
        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        }
        public double nextDouble() { return Double.parseDouble(next());}
    }
} public class Main {
    public static void main(String[] args){
        FastScanner sc = new FastScanner();
        int n = sc.nextInt();
        int[] rates = new int[n];
        long maxv = -2000000000;
        for(int i=0; i<n; i++){
            rates[i] = sc.nextInt();
        }
        /**
         * この場合,O(n^2)で n=200000 20^10　> 10^8   
         * for(int j=1; j<n; j++){
         *             for(int i=0; i<j; i++){
         *                 maxv = Math.max(rates[j] - rates[i], maxv);
         *             }
         *         }
         */
        
        // minvを保持することで　O(n)
        long minv = rates[0];
        for(int j=1; j<n; j++){
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        }


        System.out.println(maxv);

    }

    static class FastScanner {
        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;
        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }
        private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
        private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
        public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
        public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }
        public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }
        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        }
        public double nextDouble() { return Double.parseDouble(next());}
    }
} Main
import java.io.IOException;
import java.io.InputStream;
import java.util.*;

public class Main {
    public static void main(String[] args){
        FastScanner sc = new FastScanner();
        int n = sc.nextInt();
        int[] rates = new int[n];
        long maxv = -2000000000;
        for(int i=0; i<n; i++){
            rates[i] = sc.nextInt();
        }
        /**
         * この場合,O(n^2)で n=200000 20^10　> 10^8   
         * for(int j=1; j<n; j++){
         *             for(int i=0; i<j; i++){
         *                 maxv = Math.max(rates[j] - rates[i], maxv);
         *             }
         *         }
         */
        
        // minvを保持することで　O(n)
        long minv = rates[0];
        for(int j=1; j<n; j++){
            maxv = Math.max(maxv, rates[j] - minv);
            minv = Math.min(minv, rates[j]);
        }


        System.out.println(maxv);

    }

    static class FastScanner {
        private final InputStream in = System.in;
        private final byte[] buffer = new byte[1024];
        private int ptr = 0;
        private int buflen = 0;
        private boolean hasNextByte() {
            if (ptr < buflen) {
                return true;
            }else{
                ptr = 0;
                try {
                    buflen = in.read(buffer);
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (buflen <= 0) {
                    return false;
                }
            }
            return true;
        }
        private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}
        private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}
        public boolean hasNext() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++; return hasNextByte();}
        public String next() {
            if (!hasNext()) throw new NoSuchElementException();
            StringBuilder sb = new StringBuilder();
            int b = readByte();
            while(isPrintableChar(b)) {
                sb.appendCodePoint(b);
                b = readByte();
            }
            return sb.toString();
        }
        public long nextLong() {
            if (!hasNext()) throw new NoSuchElementException();
            long n = 0;
            boolean minus = false;
            int b = readByte();
            if (b == '-') {
                minus = true;
                b = readByte();
            }
            if (b < '0' || '9' < b) {
                throw new NumberFormatException();
            }
            while(true){
                if ('0' <= b && b <= '9') {
                    n *= 10;
                    n += b - '0';
                }else if(b == -1 || !isPrintableChar(b)){
                    return minus ? -n : n;
                }else{
                    throw new NumberFormatException();
                }
                b = readByte();
            }
        }
        public int nextInt() {
            long nl = nextLong();
            if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) throw new NumberFormatException();
            return (int) nl;
        }
        public double nextDouble() { return Double.parseDouble(next());}
    }
}
