2
1 18
 9
6 20 27 28 40 53 59 70 85
 8
10 20 30 40 50 60 70 80
 6
13 17 32 47 60 66
 1
1
 8
5 17 20 35 42 53 67 76
 1
90
 6
14 29 43 59 70 74
 76
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
 8
15 20 30 40 50 60 73 83
 14
14 22 27 31 35 44 46 61 62 69 74 79 88 89
 30
6 11 12 15 22 24 30 31 32 33 34 35 40 42 44 45 47 50 53 54 57 58 63 67 75 77 79 81 83 88
 84
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84
 6
15 30 45 60 74 89
 9
15 28 39 48 55 60 63 64 74
 1
15
 9
10 20 30 40 50 60 70 80 84
 25
1 2 3 4 5 6 7 8 9 10 11 23 36 50 65 81 82 83 84 85 86 87 88 89 90
 5
15 30 45 60 74
 2
16 50
 12
14 22 27 31 35 44 62 69 74 79 88 89
 10
15 28 39 48 55 60 63 64 74 82
 60
1 2 4 5 6 7 11 14 16 18 20 21 22 23 24 25 26 33 34 35 36 37 38 39 41 42 43 44 46 47 48 49 52 55 56 57 58 59 60 61 63 64 65 67 68 70 71 72 73 74 75 77 78 80 82 83 84 85 86 88
 6
15 30 45 60 75 84
 90
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
 3
1 20 90
 8
1 16 30 31 32 33 34 50
 72
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89
 12
1 3 6 10 15 21 28 36 45 55 66 78
 1
16
 5
15 30 45 60 75

16
 90
 90
 81
 16
 90
 15
 58
 90
 90
 90
 90
 90
 90
 89
 30
 90
 80
 89
 15
 59
 90
 90
 90
 90
 16
 49
 54
 90
 15
 90

import java.io.*;
import java.util.*;
import java.util.function.Function;
import java.util.function.ToDoubleFunction;
import java.util.function.ToIntFunction;
import java.util.function.ToLongFunction;

import static java.lang.Integer.*;

public class Solution {

    class Pair<K, V> implements Serializable {
        K key;
        V value;

        public V getValue() {
            return value;
        }

        public void setValue(V value) {
            this.value = value;
        }

        public K getKey() {
            return key;
        }

        public void setKey(K key) {
            this.key = key;
        }

        @Override
        public String toString() {
            return key + " " + value;
        }

        @Override
        public int hashCode() {
            return key.hashCode() * 13 + (value == null ? 0 : value.hashCode());
        }

        @Override
        public boolean equals(Object obj) {
            if (this == obj) return true;
            if (obj instanceof Pair) {
                Pair pair = (Pair) obj;
                if (key != null ? !key.equals(pair.key) : pair.key != null) return false;
                if (value != null ? !value.equals(pair.value) : pair.value != null) return false;
                return true;
            }
            return false;
        }
    }

    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    PrintWriter out = new PrintWriter(System.out);
    StringTokenizer stringTokenizer;
    Scanner scan = new Scanner(System.in);

    String next() throws IOException {
        while (stringTokenizer == null || !stringTokenizer.hasMoreTokens()) {
            String line = in.readLine();
            if (line == null) {
                throw new IOException();
            }

            stringTokenizer = new StringTokenizer(line);
        }
        return stringTokenizer.nextToken();
    }

    int nextInt() throws IOException {
        return parseInt(next());
    }

    long nextLong() throws IOException {
        return Long.parseLong(next());
    }

    double nextDouble() throws IOException {
        return Double.parseDouble(next());
    }

    public static void main(String... args) throws IOException {
        new Solution().run();
    }

    private void run() throws IOException {
        int n = nextInt();
        int[] a = new int[n + 1];
        a[0] = 0;

        for (int i = 1; i < a.length; i++)
            a[i] = nextInt();

        int delta = 15;

        for (int i = 1; i < a.length; i++) {
            if (a[i] - a[i - 1] > 15)
                break;
            else
                delta = a[i] == 90 ? 90 : 15 + a[i];
        }

        System.out.println(delta);
    }
}
