n, a, b = list(map(int, input().split()))
inf = 1<<60
dp = [[inf for _ in range(a+1)] for _ in range(n+1)]
dp[0][0] = 0
for _ in range(n):
	a0, b0 = list(map(int, input().split()))
	for ni in range(n, 0, -1):
		for ai in range(a0, a+1):
			dp[ni][ai] = min(dp[ni][ai], dp[ni-1][ai-a0]+b0)
for ni in range(n, -1, -1):
	if min(dp[ni]) <= b:
		print(ni)
		break