function Main(input) {
    var inp = input.split("\n");
    var s = inp[1];
    var ab = inp[0].split(' ').map(n => parseInt(n));
    var a = ab[0];
    var b = ab[1];
    var count = 0;
    for (i = 0; i <= a+b; i++) {
        if(0 <= i && i < a) {
            if(!isNaN(s[i])) {
                count++;
            }
        } else if(a < i && i <= a+b) {
            if(!isNaN(s[i])) {
                count++;
            }
        } else if(i === a) {
            if(s[i] === '-') {
                count++;
            }
        } 
    }
    if (count === 8) {
        console.log('Yes');
    } else {
        console.log('No');
    }
 
    
    }
Main(require('fs').readFileSync('/dev/stdin', 'utf8'));