N,M,P,Q = map(int,input().split())
for _ in range(Q):
    x,f = map(int,input().split())
    x = x%P
    y = (pow(x,P-2,P)*f)%P
    if x==0 and f!=0:
        print(0)
    elif x==0 and f==0:
        print(M)
    else:
        if y>M:
            print(0)
        else:
            ans = (M-y)//P+1
            if y==0:
                print(ans-1)
            else:
                print(ans)