import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws IOException {
        InputReader in = new InputReader();
        PrintWriter out = new PrintWriter(System.out);
        int t = 1;
        Solver s = new Solver();
        for (int i = 1; i <= t; i++) {
            s.solve(i, in, out);
        }
        out.close();
    }

}

class Solver {
    void solve(int test, InputReader in, PrintWriter out) throws IOException {
        int a = in.nextInt();
        int b = in.nextInt();
        String s = in.next();
        for (int i = 0; i < s.length(); i++) {
            if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            }
        }
        out.println("Yes");
    }
}

class InputReader {
    BufferedReader br;
    StringTokenizer st;

    public InputReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
        st = null;
    }

    public String next() {
        while (st == null || !st.hasMoreTokens()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return st.nextToken();
    }

    public int nextInt() {
        return Integer.parseInt(next());
    }

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

    public String nextLine() throws IOException {
        return br.readLine();
    }

    public double nextDouble() {
        return Double.parseDouble(next());
    }
} import java.io.*; io.* java import java.util.*; util.* java public class Main {
    public static void main(String[] args) throws IOException {
        InputReader in = new InputReader();
        PrintWriter out = new PrintWriter(System.out);
        int t = 1;
        Solver s = new Solver();
        for (int i = 1; i <= t; i++) {
            s.solve(i, in, out);
        }
        out.close();
    }

} Main public static void main(String[] args) throws IOException {
        InputReader in = new InputReader();
        PrintWriter out = new PrintWriter(System.out);
        int t = 1;
        Solver s = new Solver();
        for (int i = 1; i <= t; i++) {
            s.solve(i, in, out);
        }
        out.close();
    } main {
        InputReader in = new InputReader();
        PrintWriter out = new PrintWriter(System.out);
        int t = 1;
        Solver s = new Solver();
        for (int i = 1; i <= t; i++) {
            s.solve(i, in, out);
        }
        out.close();
    } InputReader in = new InputReader(); in new InputReader() PrintWriter out = new PrintWriter(System.out); out new PrintWriter(System.out) int t = 1; t 1 Solver s = new Solver(); s new Solver() for (int i = 1; i <= t; i++) {
            s.solve(i, in, out);
        } int i = 1; int i = 1; i 1 i <= t i t i++ i++ i {
            s.solve(i, in, out);
        } {
            s.solve(i, in, out);
        } s.solve(i, in, out) s.solve s i in out out.close() out.close out String[] args args class Solver {
    void solve(int test, InputReader in, PrintWriter out) throws IOException {
        int a = in.nextInt();
        int b = in.nextInt();
        String s = in.next();
        for (int i = 0; i < s.length(); i++) {
            if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            }
        }
        out.println("Yes");
    }
} Solver void solve(int test, InputReader in, PrintWriter out) throws IOException {
        int a = in.nextInt();
        int b = in.nextInt();
        String s = in.next();
        for (int i = 0; i < s.length(); i++) {
            if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            }
        }
        out.println("Yes");
    } solve {
        int a = in.nextInt();
        int b = in.nextInt();
        String s = in.next();
        for (int i = 0; i < s.length(); i++) {
            if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            }
        }
        out.println("Yes");
    } int a = in.nextInt(); a in.nextInt() in.nextInt in int b = in.nextInt(); b in.nextInt() in.nextInt in String s = in.next(); s in.next() in.next in for (int i = 0; i < s.length(); i++) {
            if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            }
        } int i = 0; int i = 0; i 0 i < s.length() i s.length() s.length s i++ i++ i {
            if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            }
        } {
            if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            }
        } if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            } i == a i a {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                } s.charAt(i) != '-' s.charAt(i) s.charAt s i '-' {
                    out.println("No");
                    return;
                } out.println("No") out.println out "No" return; {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            } if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                } !Character.isDigit(s.charAt(i)) Character.isDigit(s.charAt(i)) Character.isDigit Character s.charAt(i) s.charAt s i {
                    out.println("No");
                    return;
                } out.println("No") out.println out "No" return; out.println("Yes") out.println out "Yes" int test test InputReader in in PrintWriter out out class InputReader {
    BufferedReader br;
    StringTokenizer st;

    public InputReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
        st = null;
    }

    public String next() {
        while (st == null || !st.hasMoreTokens()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return st.nextToken();
    }

    public int nextInt() {
        return Integer.parseInt(next());
    }

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

    public String nextLine() throws IOException {
        return br.readLine();
    }

    public double nextDouble() {
        return Double.parseDouble(next());
    }
} InputReader BufferedReader br; br StringTokenizer st; st public InputReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
        st = null;
    } InputReader {
        br = new BufferedReader(new InputStreamReader(System.in));
        st = null;
    } br = new BufferedReader(new InputStreamReader(System.in)) br new BufferedReader(new InputStreamReader(System.in)) st = null st null public String next() {
        while (st == null || !st.hasMoreTokens()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return st.nextToken();
    } next {
        while (st == null || !st.hasMoreTokens()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return st.nextToken();
    } while (st == null || !st.hasMoreTokens()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        } st == null || !st.hasMoreTokens() st == null st null !st.hasMoreTokens() st.hasMoreTokens() st.hasMoreTokens st {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        } try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            } catch (IOException e) {
                throw new RuntimeException(e);
            } IOException e {
                throw new RuntimeException(e);
            } throw new RuntimeException(e); new RuntimeException(e) {
                st = new StringTokenizer(br.readLine());
            } st = new StringTokenizer(br.readLine()) st new StringTokenizer(br.readLine()) return st.nextToken(); st.nextToken() st.nextToken st public int nextInt() {
        return Integer.parseInt(next());
    } nextInt {
        return Integer.parseInt(next());
    } return Integer.parseInt(next()); Integer.parseInt(next()) Integer.parseInt Integer next() next public long nextLong() {
        return Long.parseLong(next());
    } nextLong {
        return Long.parseLong(next());
    } return Long.parseLong(next()); Long.parseLong(next()) Long.parseLong Long next() next public String nextLine() throws IOException {
        return br.readLine();
    } nextLine {
        return br.readLine();
    } return br.readLine(); br.readLine() br.readLine br 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) throws IOException {
        InputReader in = new InputReader();
        PrintWriter out = new PrintWriter(System.out);
        int t = 1;
        Solver s = new Solver();
        for (int i = 1; i <= t; i++) {
            s.solve(i, in, out);
        }
        out.close();
    }

} public class Main {
    public static void main(String[] args) throws IOException {
        InputReader in = new InputReader();
        PrintWriter out = new PrintWriter(System.out);
        int t = 1;
        Solver s = new Solver();
        for (int i = 1; i <= t; i++) {
            s.solve(i, in, out);
        }
        out.close();
    }

} Main
import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) throws IOException {
        InputReader in = new InputReader();
        PrintWriter out = new PrintWriter(System.out);
        int t = 1;
        Solver s = new Solver();
        for (int i = 1; i <= t; i++) {
            s.solve(i, in, out);
        }
        out.close();
    }

}

class Solver {
    void solve(int test, InputReader in, PrintWriter out) throws IOException {
        int a = in.nextInt();
        int b = in.nextInt();
        String s = in.next();
        for (int i = 0; i < s.length(); i++) {
            if (i == a) {
                if (s.charAt(i) != '-') {
                    out.println("No");
                    return;
                }
            } else {
                if (!Character.isDigit(s.charAt(i))) {
                    out.println("No");
                    return;
                }
            }
        }
        out.println("Yes");
    }
}

class InputReader {
    BufferedReader br;
    StringTokenizer st;

    public InputReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
        st = null;
    }

    public String next() {
        while (st == null || !st.hasMoreTokens()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return st.nextToken();
    }

    public int nextInt() {
        return Integer.parseInt(next());
    }

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

    public String nextLine() throws IOException {
        return br.readLine();
    }

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