#include <bits/stdc++.h>
using namespace std;
 
#define fi first
#define se second
#define pb push_back
using vi = vector <int>;
using ll = long long;
using vl = vector <ll>;
using pii = pair <int, int>;
const ll mod = 998244353;
//~ const ll mod = 1e9 + 7;
ll qpow(ll a, ll b, ll m = mod) { ll r = 1, t = a;
	for(; b; b /= 2) { if(b & 1) r = r * t % m; t = t * t % m; } return r; }

const int N = 5e3 + 11;

int f[N][N], g[N][N];

pii pizza[N]; // {p, d}
void upd(int &a, int b) {
	if(a < b) a = b;
}

int main() {
	ios::sync_with_stdio(0);
	int n, k; cin >> n >> k;
	for(int i = 1; i <= n; i ++)
		cin >> pizza[i].fi >> pizza[i].se;
	
	sort(pizza + 1, pizza + n + 1);
	
	for(int i = 0; i < n; i ++) {
		auto [p, d] = pizza[i + 1];
		for(int j = 0; j <= k; j ++) {
			upd(f[i + 1][j], f[i][j]);
			upd(g[i + 1][j], g[i][j]);
			
			upd(g[i + 1][j], f[i][j] + d);
			if(j + p <= k)
				upd(f[i + 1][j + p], g[i][j] + d);
		}
	}
	
	int ans = 0;
	for(int j = 0; j <= k; j ++)
		upd(ans, f[n][j]);
	cout << ans << '\n';
}