n,m,p,q=map(int,input().split())
for _ in range(q):
  x,f=map(int,input().split())
  if f==0:
    if x%p==0:
      print(m)
    else:
      print(m//p)
  else:
    inv=f*pow(x,p-2,p)%p
    print((m-inv+p)//p)