Submission #1195023

#	Time	Username	Problem	Language	Result	Execution time	Memory
1195023		nikulid	Ideal city (IOI12_city)	C++20	0 / 100	145 ms	327680 KiB

city

#include <climits>
#include <vector>
/*
  
  lemma: I will solve subtasks 1 and 2
  proof:

*/
using namespace std;

long long ans=0;
vector<vector<int>> visitted, exists; // both are [y][x]
vector<vector<bool>> DONE;
void bfs(int I, int x, int y, int curdist){
  // coords is [x,y]
  visitted[y][x] = I;
  if(exists[y+1][x+1] && visitted[y+1][x+1] != I){
    ans += curdist+1;
    ans /= 2;
    bfs(I, x+1, y+1, curdist+1);
  }
  if(exists[y+1][x-1] && visitted[y+1][x-1] != I){
    ans += curdist+1;
    ans /= 2;
    bfs(I, x-1, y+1, curdist+1);
  }
  if(exists[y-1][x+1] && visitted[y-1][x+1] != I){
    ans += curdist+1;
    ans /= 2;
    bfs(I, x+1, y-1, curdist+1);
  }
  if(exists[y-1][x-1] && visitted[y-1][x-1] != I){
    ans += curdist+1;
    ans /= 2;
    bfs(I, x-1, y-1, curdist+1);
  }
  return;
}

int DistanceSum(int N, int *X, int *Y) {
  DONE = vector<vector<bool>>(N+1, vector<bool>(N+1, 0));
  visitted = vector<vector<int>>(N+1, vector<int>(N+1, 0));
  exists = vector<vector<int>>(N+1, vector<int>(N+1, 0));

  // find min X and Y values, to translate the graph to start at (1,1)
  int minX=INT_MAX-1, minY=INT_MAX-1;
  for(int i=0; i<N; i++){
    minX = min(minX, X[i]);
    minY = min(minY, Y[i]);
  }
  for(int i=0; i<N; i++){
    exists[Y[i]-minY][X[i]-minX] = 1;
  }

  for(int i=0; i<N; i++){
    bfs(i, X[i]-minX, Y[i]-minY, 0);
  }
  ans /= 2;
  ans %= 1000000000;
  return ans;

}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 21
• Subtask 3: 0 / 23
• Subtask 4: 0 / 45