Problem:
Score : 200 points

Problem Statement

The postal code in Atcoder Kingdom is A+B+1 characters long, its (A+1)-th character is a hyphen -, and the other characters are digits from 0 through 9.

You are given a string S. Determine whether it follows the postal code format in Atcoder Kingdom.

Constraints

1≤A,B≤5

|S|=A+B+1

S consists of - and digits from 0 through 9.

Input

Input is given from Standard Input in the following format:

A B
S

Output

Print Yes if S follows the postal code format in AtCoder Kingdom; print No otherwise.

Sample Input 1

3 4
269-6650

Sample Output 1

Yes

The (A+1)-th character of S is -, and the other characters are digits from 0 through 9, so it follows the format.

Sample Input 2

1 1
---

Sample Output 2

No

S contains unnecessary -s other than the (A+1)-th character, so it does not follow the format.

Sample Input 3

1 2
7444

Sample Output 3

No

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <iomanip>
#include <algorithm>
#include <map>
#include <numeric>
#include <queue>
#include <stack>
#include <sstream>
#include <string>
#include <vector>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <cassert>

using ll = long long;
//typedef long long ll;

using std::cin;
using std::cout;
using std::cerr;
using std::endl;

#define INF ((1LL << 31) - 1)
#define INFLL ((1LL << 62) - 1)
#define MOD (ll)(1e9+7)
#define EPS 1e-10
#define repi(i,j,n) for(int i = (j); i < (n); ++i)
#define rep(i,n) repi(i,0,n)
#define rrep(i,n) for(int i = n; i >= 0; --i)
#define fi first
#define se second
#define all(v) (v).begin(), (v).end()

int vx[4] = {-1, 0, 1, 0}, vy[4] = {0, -1, 0, 1};
//int vx[8] = {0, 1, 1, 1, 0, -1, -1, -1}, vy[8] = {-1, -1, 0, 1, 1, 1, 0, -1};

// [sx, se), [sy, ey)であることに注意
inline bool check(int sx, int ex, int sy, int ey, int x, int y) {
  return (sx <= x and x < ex and sy <= y and y < ey);
}

inline bool check(int ex, int ey, int x, int y) {
  return check(0, ex, 0, ey, x, y);
}

std::vector<std::string> split(const std::string& s, char delim) {
  std::vector<std::string> ret;
  std::stringstream ss(s);
  std::string tmp;

  while (std::getline(ss, tmp, delim)) {
    ret.push_back(tmp);
  }

  return ret;
}

inline void init() {
  cin.tie(0);
  std::ios::sync_with_stdio(false);
}

int main() {
  int a, b;
  std::string s;

  cin >> a >> b;
  cin >> s;

  for (int i = 0; i < s.size(); ++i) {
    if (i == a) {
      if (s[i] != '-') {
        cout << "No" << endl;
        return 0;
      }
    } else {
      if (s[i] == '-') {
        cout << "No" << endl;
        return 0;
      }
    }
  }

  cout << "Yes" << endl;
  return 0;
}