R=range
J=lambda:map(int,input().split())
N,A,B=J()
X=[list(J())for i in R(N)]
D=[[B+1]*A*2for i in R(N+1)]
D[0][0]=0
for x,y in X:
	for c in R(N,0,-1):
		for a in R(A,x-1,-1):D[c][a]=min(D[c][a],D[c-1][a-x]+y)
print(max(c for c in R(N+1)if min(D[c])<=B))