# -*- coding: utf-8 -*-

import math

A,B = input().split(" ")
s = str(input())

s_sp = s.split("-")

if (len(s_sp) != 2):
    print("No")
    exit

if (len(s_sp[0]) != int(A)) | (len(s_sp[1]) != int(B)):
    print("No")
    exit

if ((s_sp[0].isdigit()) & (s_sp[1].isdigit())):
    print("Yes")
else:
    print("No")
