#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for (int i = 0; i < (n); ++i)
typedef long long ll;
const long long INF = 1e18;

void chmax(ll *a,ll b){
    if (*a<b) *a=b;
    return;
}

int main(){
    ll N,K;
    cin>>N>>K;
    vector<ll> p(N),d(N);
    rep(i,N) cin>>p[i]>>d[i];
    vector<vector<vector<ll>>> dp(2,vector<vector<ll>>(N+1,vector<ll>(K+1,0)));
    rep(i,N)rep(j,K+1){
        chmax(&dp[0][i+1][j],dp[0][i][j]);
        if (j+d[i]<=K) chmax(&dp[1][i+1][j+p[i]],dp[0][i][j]+d[i]);
        if (dp[1][i][j]==0) continue;
        chmax(&dp[1][i+1][j],dp[1][i][j]);
        chmax(&dp[0][i+1][j],dp[1][i][j]+d[i]);
    }
    cout<<(dp[0][N][K]<dp[1][N][K] ? dp[1][N][K] : dp[0][N][K])<<endl;
    return 0;
}