#include<cstdio>
#include<algorithm>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); ++i)
#define rrep(i, n) for (int i = (int)(n)-1; i >= 0; --i)
#define rep2(i, a, b) for (int i = (int)a; i < (int)(b); ++i)
#define rrep2(i, a, b) for (int i = (int)(b)-1; i >= (int)(a); --i)
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
constexpr int INF = -1000000;
int main(){
    int N, I;
    scanf("%d %d", &N, &I);
    int dp[I+1];
    fill(dp,dp+I+1,INF);
    dp[0] = 0;
    rep(_,N){
        int S, A;
        scanf("%d %d", &S, &A);
        rrep(i, I-S+1) chmax(dp[i + S], dp[i] + A);
    }
    printf("%d\n", *max_element(dp,dp+I+1));
}