import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.PriorityQueue;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskE solver = new TaskE();
        solver.solve(1, in, out);
        out.close();
    }

    static class TaskE {
        public void solve(int testNumber, InputReader in, PrintWriter out) {
            int n = in.readInt();
            int k = in.readInt();
            int q = in.readInt();
            int[] a = in.readIntArray(n);
            int ans = Integer.MAX_VALUE;
            for (int i = 0; i < n; i++) {
                int last = 0;
                PriorityQueue<Integer> queue = new PriorityQueue<>();
                for (int j = 0; j < n; j++) {
                    if (a[j] < a[i]) {
                        insert(a, last, j - 1, queue, k);
                        last = j + 1;
                    }
                }
                insert(a, last, n - 1, queue, k);
                if (queue.size() < q) continue;
                int min = queue.poll();
                int max = 0;
                for (int j = 1; j < q; j++) {
                    max = queue.poll();
                }
                ans = Math.min(ans, max - min);
            }
            if (ans == Integer.MAX_VALUE) throw new RuntimeException();
            out.println(ans);


        }

        void insert(int[] a, int l, int r, PriorityQueue<Integer> queue, int k) {
            int m = r - l + 1;
            if (m < k) return;
            int[] b = new int[m];
            for (int i = l; i <= r; i++) {
                b[i - l] = a[i];
            }
            Arrays.sort(b);
            for (int i = 0; i < m - k + 1; i++) queue.add(b[i]);
        }

    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private InputReader.SpaceCharFilter filter;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int read() {
            if (numChars == -1)
                throw new InputMismatchException();
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0)
                    return -1;
            }
            return buf[curChar++];
        }

        public int readInt() {
            int c = read();
            while (isSpaceChar(c))
                c = read();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = read();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c - '0';
                c = read();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public boolean isSpaceChar(int c) {
            if (filter != null)
                return filter.isSpaceChar(c);
            return isWhitespace(c);
        }

        public static boolean isWhitespace(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        public int[] readIntArray(int size) {
            int[] ans = new int[size];
            for (int i = 0; i < size; i++) ans[i] = readInt();
            return ans;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);

        }

    }
}

