#include <iostream>

using namespace std;
using LL = long long;

int dp[1001];

int main() {
    int N, I;
    cin >> N >> I;

    for (int i = 0; i <= I; i++) dp[i] = -1;

    dp[0] = 0;
    int s, a;
    for (int i = 0; i < N; i++) {
        cin >> s >> a;
        for (int j = I - s; j >= 0; j--) {
            if (dp[j] != -1) {
                dp[j + s] = max(dp[j + s], dp[j] + a);
            }
        }
    }

    int ans = 0;
    for (int i = I; i >= 0; i--) {
        ans = max(ans, dp[i]);
    }

    cout << ans << endl;
}