#include <bits/extc++.h>

int main() {
    using namespace std;
    unsigned long N, I;
    cin >> N >> I;
    vector<optional<unsigned long>> ans(I + 1);
    ans[0] = 0;
    for(unsigned long i{}, s, a; i < N; ++i){
        cin >> s >> a;
        for(unsigned long j{I}; j >= s; --j)if(ans[j - s])ans[j] = max(ans[j].value_or(0), a + ans[j - s].value());
    }
    cout << max_element(begin(ans), end(ans)) -> value() << endl;
    return 0;
}