#ifdef LOCAL111
	#define _GLIBCXX_DEBUG
#else
	#pragma GCC optimize ("O3")
	#define NDEBUG
#endif
// #define _USE_MATH_DEFINES
#include <bits/stdc++.h>
const int INF = 1e9;
using namespace std;
template<typename T, typename U> ostream& operator<< (ostream& os, const pair<T,U>& p) { os << '(' << p.first << ' ' << p.second << ')'; return os; }

#define endl '\n'
#define ALL(a)  (a).begin(),(a).end()
#define SZ(a) int((a).size())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n)  FOR(i,0,n)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)
#ifdef LOCAL111
	#define DEBUG(x) cout<<#x<<": "<<(x)<<endl
	template<typename T> void dpite(T a, T b){ for(T ite = a; ite != b; ite++) cout << (ite == a ? "" : " ") << *ite; cout << endl;}
#else
	#define DEBUG(x) true
	template<typename T> void dpite(T a, T b){ return; }
#endif
#define F first
#define S second
#define SNP string::npos
#define WRC(hoge) cout << "Case #" << (hoge)+1 << ": "
template<typename T> void pite(T a, T b){ for(T ite = a; ite != b; ite++) cout << (ite == a ? "" : " ") << *ite; cout << endl;}
template<typename T> bool chmax(T& a, T b){if(a < b){a = b; return true;} return false;}
template<typename T> bool chmin(T& a, T b){if(a > b){a = b; return true;} return false;}

template<typename T>
vector<T> make_v(size_t a){return vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

template<typename T,typename U,typename... V>
typename enable_if<is_same<T, U>::value!=0>::type
fill_v(U &u,const V... v){u=U(v...);}

template<typename T,typename U,typename... V>
typename enable_if<is_same<T, U>::value==0>::type
fill_v(U &u,const V... v){
  for(auto &e:u) fill_v<T>(e,v...);
}

const array<int, 4> dx = {0, 1, 0, -1};
const array<int, 4> dy = {1, 0, -1, 0};


typedef long long int LL;
typedef unsigned long long ULL;
typedef pair<int,int> P;

void ios_init(){
	//cout.setf(ios::fixed);
	//cout.precision(12);
#ifdef LOCAL111
	return;
#endif
	ios::sync_with_stdio(false); cin.tie(0);
}

int main()
{
	ios_init();
	int n, k;
	while(cin >> n >> k) {
		vector<int> p(n), d(n);
		REP(i, n) cin >> p[i] >> d[i];
		vector<P> pd(n);
		REP(i, n) pd[i] = {p[i], d[i]};
		sort(ALL(pd)); reverse(ALL(pd));
		dpite(ALL(pd));
		auto dp = make_v<int>(k + 1, 2);
		REP(j, k + 1) REP(b, 2) dp[j][b] = -INF;
		dp[0][0] = 0;
		REP(i, n) {
			DEBUG(i);
			auto nex = dp;
			REP(j, k + 1) {
				chmax(nex[j][0], dp[j][1] + pd[i].S);
				if(j + pd[i].F <= k) {
					chmax(nex[j + pd[i].F][1], dp[j][0] + pd[i].S);
				}
			}
			dp = nex;
		}
		int ans = 0;
		REP(j, k + 1) chmax(ans, max(dp[j][0], dp[j][1]));
		cout << ans << endl;

	}
	return 0;
}