import java.io.InputStream;
import java.io.IOException;
import java.util.NoSuchElementException;
import static java.lang.System.*;

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 fs = new FastScanner();

    int a = fs.nextInt();
    int b = fs.nextInt();
    String s = fs.next();

    String[] list = s.split("-", 0);
    if (list.length == 2 && list[0].length() == a && list[1].length() == b)
      out.println("Yes");
    else
      out.println("No");
  }
}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz