#include <algorithm>
#include <bitset>
#include <cassert>
#include <cctype>
#include <chrono>
#define _USE_MATH_DEFINES
#include <cmath>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <utility>
#include <vector>
using namespace std;

#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()

const int INF = 0x3f3f3f3f;
const long long LINF = 0x3f3f3f3f3f3f3f3fLL;
const double EPS = 1e-8;
const int MOD = 1000000007;
// const int MOD = 998244353;
const int dy[] = {1, 0, -1, 0}, dx[] = {0, -1, 0, 1};
// const int dy[] = {1, 1, 0, -1, -1, -1, 0, 1},
//           dx[] = {0, -1, -1, -1, 0, 1, 1, 1};

struct IOSetup {
  IOSetup() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    cout << fixed << setprecision(20);
    cerr << fixed << setprecision(10);
  }
} iosetup;
/*-------------------------------------------------*/
int main() {
  int n, k; cin >> n >> k;
  vector<pair<int, int> > pd(n); REP(i, n) cin >> pd[i].first >> pd[i].second;
  sort(pd.rbegin(), pd.rend());
  vector<vector<vector<int> > > dp(2, vector<vector<int> >(k + 1, vector<int>(2, -INF)));
  dp[0][0][false] = 0;
  REP(i, n) REP(j, k + 1) {
    REP(l, 2) dp[(i + 1) & 1][j][l] = max(dp[(i + 1) & 1][j][l], dp[i & 1][j][l]);
    if (j + pd[i].first <= k) dp[(i + 1) & 1][j + pd[i].first][true] = max(dp[(i + 1) & 1][j + pd[i].first][true], dp[i & 1][j][false] + pd[i].second);
    dp[(i + 1) & 1][j][false] = max(dp[(i + 1) & 1][j][false], dp[i & 1][j][true] + pd[i].second);
  }
  int ans = 0;
  REP(j, k + 1) ans = max({ans, dp[n & 1][j][false], dp[n & 1][j][true]});
  cout << ans << '\n';
  return 0;
}