#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;

//template
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(a);i>(b);i--)
#define ALL(v) (v).begin(),(v).end()
typedef long long int ll; const int inf = 0x3fffffff; const ll INF = 0x3fffffffffffffff;
template<class T> inline bool chmax(T& a,T b){ if(a<b){a=b;return 1;}return 0; }
template<class T> inline bool chmin(T& a,T b){ if(a>b){a=b;return 1;}return 0; }
//template end

typedef pair<int,int> P;
int dp[5010][5010][2]={}; //idx,sum,isfree

int main(){
    int n,k; scanf("%d%d",&n,&k);
    vector<P> p(n);
    rep(i,0,n)scanf("%d%d",&p[i].first,&p[i].second);
    sort(ALL(p));
    rep(i,0,n){
        rep(l,0,k+1)dp[i+1][l][0]=dp[i][l][0],dp[i+1][l][1]=dp[i][l][1];
        rrep(l,k,-1){
            chmax(dp[i+1][l][0],dp[i][l][1]+p[i].second);
            chmax(dp[i+1][min(5005,l+p[i].first)][1],dp[i][l][0]+p[i].second);
        }
    }
    int ans=0;
    rep(i,0,k+1)chmax(ans,dp[n][i][1]);
    printf("%d\n",ans);
    return 0;
}