// #define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#include <atcoder/all>
using namespace atcoder;
using ll = long long;
using vi = vector<int>;
using vvi = vector<vector<int>>;
using pii = pair<int, int>;
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define repr(i, n) for (int i = (int)(n - 1); i >= 0; --i)

inline void chmax(int &a, int b) {
    if (b > a) a = b;
}
int main() {
    int n, I;
    cin >> n >> I;
    vi s(n), a(n);
    rep(i, n) cin >> s[i] >> a[i];
    vi dp(I + 1, 0);
    rep(i, n) {
        repr(j, I - s[i] + 1) chmax(dp[j + s[i]], dp[j] + a[i]);
    }
    cout << dp[I] << endl;
    return 0;
}