list1 = input().split(' ') list2 = input().split(' ') n, s, a, b = int(list1[0]), int(list1[1]), int(list2[0]), int(list2[1]) listEnd, sum0 = [], 0

for i in range(n): list0 = input().split(' ') if a + b >= int(list0[0]): listEnd.append(list0) listEnd = sorted(listEnd, key=lambda x: x[1])

print(listEnd)

for j in listEnd: s -= int(j[1]) if s >= 0: sum0 += 1 else: break print(sum0)