#include <bits/stdc++.h>
using namespace std;

int main() {
  cin.tie(nullptr);
  ios::sync_with_stdio(false);
  int n, k;
  cin >> n >> k;
  vector<int> p(n), d(n);
  for (int i = 0; i < n; ++i) {
    cin >> p[i] >> d[i];
  }
  vector<int> idx(n);
  iota(begin(idx), end(idx), 0);
  sort(begin(idx), end(idx), [&](int i, int j) { 
    return p[i] > p[j]; 
  });
  auto chmax = [](auto&& l, auto r) { l = max(l, r); };
  vector< vector<int> > dp(2, vector<int>(k + 1, -1e9));
  dp[0][0] = 0;
  for (int i : idx) {
    auto ndp = dp;
    for (int x = 0; x <= k; ++x) {
      if (x + p[i] <= k) {
        chmax(ndp[1][x + p[i]], dp[0][x] + d[i]);
      }
      chmax(ndp[0][x], dp[1][x] + d[i]);
    }
    swap(dp, ndp);
  }
  int res = 0;
  for (auto v : dp) {
    chmax(res, *max_element(begin(v), end(v)));
  }
  cout << res << '\n';
}