#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
int main() {
	cin.tie(0);
	ios_base::sync_with_stdio(false);
	int N, K;
	cin >> N >> K;
	vector<int> P(N), D(N), perm(N);
	for (int i = 0; i < N; ++i) {
		cin >> P[i] >> D[i];
		perm[i] = i;
	}
	sort(perm.begin(), perm.end(), [&](int i, int j) { return P[i] > P[j]; });
	vector<int> dp0(K + 1), dp1(K + 1, -(1 << 30));
	for (int i = 0; i < N; ++i) {
		for (int j = K; j >= 0; --j) {
			dp0[j] = max(dp0[j], dp1[j] + D[perm[i]]);
			if (j >= P[perm[i]]) {
				dp1[j] = max(dp1[j], dp0[j - P[perm[i]]] + D[perm[i]]);
			}
		}
	}
	cout << max(dp0[K], dp1[K]) << endl;
	return 0;
}