n, A = map(int, input().split())
a = []
for i in range(n):
    k, l = map(int, input().split())
    a.append((k, l))
a = sorted(a, key=lambda a: a[0])
count = 0
while count < n and A >= a[count][0]:
    A += a[count][1]
    count += 1
print(count)