a,b = map(int,input().split())
s=list(input())

c = 0
for i in range(0,a):
    if s[i] == '0' or'1' or '2' or '3' or'4' or'5'or '6' or '7' or '8' or '9':
        c = c+1
if s[a] == '-':
    c = c + 1
for i in range(0,b):
     if s[i+a+1] ==  '0' or'1' or '2' or '3' or'4' or'5'or '6' or '7' or '8' or '9':
        c = c+1
if c == a+b+1:
    print('Yes')
else:
    print('No')