/* AUTHOR: TUAN ANH - BUI */ // ~~ icebear ~~ #include <bits/stdc++.h> using namespace std; typedef long long ll; typedef pair<int, int> ii; typedef pair<int, ii> iii; template<class X, class Y> bool minimize(X &x, const Y &y) { if (x > y) return x = y, true; return false; } template<class X, class Y> bool maximize(X &x, const Y &y) { if (x < y) return x = y, true; return false; } #define FOR(i,a,b) for(int i=(a); i<=(b); ++i) #define FORR(i,a,b) for(int i=(a); i>=(b); --i) #define REP(i, n) for(int i=0; i<(n); ++i) #define RED(i, n) for(int i=(n)-1; i>=0; --i) #define MASK(i) (1LL << (i)) #define BIT(S, i) (((S) >> (i)) & 1) #define mp make_pair #define pb push_back #define fi first #define se second #define all(x) x.begin(), x.end() #define task "icebear" /*END OF TEMPLATE. ICEBEAR AND THE CAT WILL WIN VOI26 */ const int MOD = 1e9 + 7; const int inf = (int)1e9 + 27092008; const ll INF = (ll)1e18 + 27092008; const int N = 2000 + 5; int numPiece, numChoose; ii piece[N]; ll f[N][N]; void init(void) { cin >> numPiece >> numChoose; FOR(i, 1, numPiece) cin >> piece[i].fi >> piece[i].se; } void process(void) { sort(piece + 1, piece + numPiece + 1, [&](const ii &x, const ii &y){return x.se < y.se;}); FOR(i, 0, numPiece) FOR(j, 0, numChoose) f[i][j] = -INF; FOR(i, 1, numPiece) FOR(j, 1, numChoose) { f[i][j] = f[i - 1][j]; if (j == 1) maximize(f[i][j], piece[i].fi + 2 * piece[i].se); else if (j < numChoose) maximize(f[i][j], f[i - 1][j - 1] + piece[i].fi); else maximize(f[i][j], f[i - 1][j - 1] + piece[i].fi - 2 * piece[i].se); } cout << f[numPiece][numChoose]; } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); if (fopen(task".inp", "r")) { freopen(task".inp", "r", stdin); freopen(task".out", "w", stdout); } int tc = 1; // cin >> tc; while(tc--) { init(); process(); } return 0; }

cake3.cpp: In function 'int main()':
cake3.cpp:67:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   67 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
cake3.cpp:68:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   68 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~