# | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
832502 | 2023-08-21T10:56:58 Z | rnl42 | Catfish Farm (IOI22_fish) | C++17 | 0 ms | 0 KB |
#include "fish.h" #include <vector> #include <algorithm> #include <iostream> using namespace std; #define int long long using piii = pair<int,pair<int,int>>; #ifdef DEBUG void dbg_out() {} template <typename Head, typename... Tail> void dbg_out(Head H, Tail... T) { cerr << H << " "; dbg_out(T...); } #define dbg(...) cerr << "(" #__VA_ARGS__ ") = "; dbg_out(__VA_ARGS__); cerr << '\n' //#define dbg(x) cerr << "(" #x ") = " << x << '\n' #define dbgln() cerr << '\n' #else #define dbg(x) void(0) #define dbgln(x) void(0) #endif int max_weights(signed N, signed M, vector<signed> X, vector<signed> Y, vector<signed> W) { vector<vector<int>> grid(N, vector<int>(N+2)); vector<vector<int>> cumulsum(N, vector<int>(N+2)); for (int i = 0; i < M; i++) grid[X[i]][Y[i]] = W[i]; for (int x = 0; x < N; x++) { for (int y = 0; y <= N; y++) { cumulsum[x][y+1] = cumulsum[x][y]+grid[x][y]; } } vector<vector<int>> best_asc(N, vector<int>(N+2, -1e18)), best_desc(N, vector<int>(N+2, -1e18)); for (int y = 0; y <= N+1; y++) { best_asc[0][y] = cumulsum[0][y+1]; } for (int x = 1; x < N; x++) { vector<int> best_for_desc(N+3, -1e18); for (int y = N+1; y >= 0; y--) { best_for_desc[y] = max(best_for_desc[y+1], best_desc[x-1][y]+cumulsum[x][y]); dbg(y, best_for_desc[y]); } int best_for_asc = 0; for (int y = 0; y <= N+1; y++) { best_for_asc = max(best_for_asc, best_asc[x-1][y]+cumulsum[x].back()-cumulsum[x][y+1]); best_asc[x][y] = cumulsum[x][y+1]; if (y <= N) best_asc[x][y] = max(best_asc[x][y], cumulsum[x][y+1]+best_desc[x-1][y+1]); best_asc[x][y] = max(best_asc[x][y], best_for_asc-(cumulsum[x].back()-cumulsum[x][y+1])); if (x >= 2) { best_desc[x][y] = max(best_desc[x][y], best_desc[x-2][N]); } if (x >= 3) { best_desc[x][y] = max(best_desc[x][y], best_desc[x-3][N]); } best_desc[x][y] = max(best_desc[x][y], best_for_desc[y]-cumulsum[x][y]); } dbgln(); } for (int x = 0; x < N; x++) { for (int y = 0; y <= N; y++) { dbg(x, y, best_asc[x][y], best_desc[x][y]); } } return max(best_desc[N-1][0], best_asc[N-2][N]); }