Submission #728809

#	Time	Username	Problem	Language	Result	Execution time	Memory
728809		kwongweng	Catfish Farm (IOI22_fish)	C++17	0 / 100	785 ms	2097152 KiB

fish

#include "fish.h"
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
typedef vector<ii> vii;
typedef long double ld;
typedef pair<ll, ll> pll;
#define FOR(i, a, b) for(int i = a; i < b; i++)
#define ROF(i, a, b) for(int i = a; i >= b; i--)
#define ms memset
#define pb push_back
#define fi first
#define se second

// O(n^2) dp

ll max_weights(int n, int m, vi X, vi Y, vi W){
  ll mat[n][n]; //position of all fishes
  ms(mat, 0, sizeof(mat));
  FOR(i,0,m){
    mat[X[i]][Y[i]] = W[i];
  }
  ll dp[n][n][2];
  // dp[i][j][0] - mat[i][j] chosen, while increasing
  // dp[i][j][1] - while decreasing
  ms(dp,0,sizeof(dp));
  FOR(i,0,n){
    //decreasing
    if (i > 0){
      FOR(k,i-3,i-1){
        dp[i][n-1][1] = max(dp[i][n-1][1], dp[k][n-1][0]);
        dp[i][n-1][1] = max(dp[i][n-1][1], dp[k][0][1]);
      }
      dp[i][n-1][1] += mat[i][n-1];
      ROF(j,n-2,0){
        dp[i][j][1] = max(dp[i][j][1], dp[i][j+1][1]);
        dp[i][j][1] = max(dp[i][j][1], dp[i-1][j+1][1]);
        dp[i][j][1] += mat[i][j];
      }
    }
    if (i < n-1){
      //increasing
      if (i>1) dp[i][0][0] = max(dp[i][0][0], dp[i-1][0][1]);
      if (i>2) dp[i][0][0] = max(dp[i][0][0], dp[i-2][n-1][0]);
      dp[i][0][0] += mat[i][0];
      FOR(j,1,n){
        dp[i][j][0] = max(dp[i][j][0], dp[i][j-1][0]);
        if (i>0){
          dp[i][j][0] = max(dp[i][j][0], dp[i-1][j-1][0]);
        }
        dp[i][j][0] += mat[i][j];
      }
    }
  }
  ll ans = 0;
  FOR(i,0,n){
    FOR(j,0,n){
      ans = max(ans, max(dp[i][j][0], dp[i][j][1]));
    }
  }
  return ans;
}

• Subtask 1: 0 / 3
• Subtask 2: 0 / 6
• Subtask 3: 0 / 9
• Subtask 4: 0 / 14
• Subtask 5: 0 / 21
• Subtask 6: 0 / 17
• Subtask 7: 0 / 14
• Subtask 8: 0 / 16