#include <iostream>
#include <algorithm>
#include <vector>

template <class T>
std::vector<T> vec(int len, T elem) { return std::vector<T>(len, elem); }

constexpr int INF = 1 << 30;

void solve() {
    int n, k;
    std::cin >> n >> k;

    std::vector<std::pair<int, int>> ps(n);
    for (auto& p : ps) std::cin >> p.first >> p.second;
    std::sort(ps.rbegin(), ps.rend());

    auto dp = vec(2, vec(k + 1, 0));
    std::fill(dp[1].begin(), dp[1].end(), -INF);
    auto ndp = dp;

    for (auto [p, d] : ps) {
        for (int i = 0; i <= k; ++i) {
            ndp[0][i] = std::max(ndp[0][i], dp[1][i] + d);
        }
        for (int i = p; i <= k; ++i) {
            ndp[1][i - p] = std::max(ndp[1][i - p], dp[0][i] + d);
        }
        dp = ndp;
    }

    std::cout << std::max(dp[0][0], dp[1][0]) << "\n";
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}