source_code: import java.io.OutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.io.PrintWriter;
  import java.io.BufferedWriter;
  import java.io.Writer;
  import java.io.OutputStreamWriter;
  import java.util.InputMismatchException;
  import java.io.IOException;
  import java.io.InputStream;
  
  /**
   * Built using CHelper plug-in Actual solution is at the top
   *
   * @author @Ziklon
   */
  public class Main {
    public static void main(String[] args) {
      InputStream inputStream = System.in;
      OutputStream outputStream = System.out;
      InputReader in = new InputReader(inputStream);
      OutputWriter out = new OutputWriter(outputStream);
      ABirthday solver = new ABirthday();
      solver.solve(1, in, out);
      out.close();
    }
  
    static class ABirthday {
      public void solve(int testNumber, InputReader in, OutputWriter out) {
        long N = in.readLong(), M = in.readLong(), K = in.readLong(), L = in.readLong();
  
        long ans = ((L + K) - 1) / M + 1;
        if (ans * M > N || ans * M - K < L) out.printLine(-1);
        else out.printLine(ans);
      }
    }
  
    static class OutputWriter {
      private final PrintWriter writer;
  
      public OutputWriter(OutputStream outputStream) {
        writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
      }
  
      public OutputWriter(Writer writer) {
        this.writer = new PrintWriter(writer);
      }
  
      public void close() {
        writer.close();
      }
  
      public void printLine(long i) {
        writer.println(i);
      }
  
      public void printLine(int i) {
        writer.println(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 long readLong() {
        int c = read();
        while (isSpaceChar(c)) {
          c = read();
        }
        int sgn = 1;
        if (c == '-') {
          sgn = -1;
          c = read();
        }
        long 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 interface SpaceCharFilter {
        public boolean isSpaceChar(int ch);
      }
    }
  }
  