s = input()  # y=-2x

for _ in range(int(input())):
    x, y = map(int, input().split())

    if "x" not in s:
        m = 0
        c = int(s)
    else:
        n = s.index("x")
        m = int(s[2:n]) 
        if n == len(s) - 1:
            c = 0
        else:
            c = int(s[(n+1):])

    if y == (m * x + c):
        print("YES")
    else:
        print("NO")