#include <iostream>
#include <algorithm>
#include <iomanip>
#include <vector>
#include <queue>
#include <set>
#include <map>

using namespace std;
typedef long long ll;
typedef pair<int, int> P_;

int dp[5005][5005][2];
int P[5000], D[5000];
P_ p[5000];
int N, K;
const int INF = 1e9;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(10) << fixed;
    cin >> N >> K;
    for(int i = 0; i < N; i++){
        cin >> P[i] >> D[i];
        p[i] = P_(P[i], D[i]);
    }
    sort(p, p+N, greater<P_>());
    for(int i = 0; i < N; i++){
        P[i] = p[i].first;
        D[i] = p[i].second;
    }

    for(int i = 0; i <= N; i++){
        for(int j = 0; j <= K; j++){
            dp[i][j][0] = -INF;
            dp[i][j][1] = -INF;
        }
    }
    dp[0][0][0] = 0;
    for(int i = 0; i < N; i++){
        for(int j = 0; j <= K; j++){
            dp[i+1][j][0] = max({dp[i+1][j][0], dp[i][j][0], dp[i][j][1]+D[i]});
            dp[i+1][j][1] = max(dp[i][j][1], dp[i+1][j][1]);
            if(j+P[i] <= K) dp[i+1][j+P[i]][1] = max({dp[i+1][j+P[i]][1], dp[i][j+P[i]][1], dp[i][j][0]+D[i]});
        }
    } 
    int ans = 0;
    for(int i = 0; i <= K; i++){
        ans = max(ans, dp[N][i][0]);
        ans = max(ans, dp[N][i][1]);
    }
    cout << ans << endl;
}