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This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters. Learn more about bidirectional Unicode charactersOriginal file line number Diff line number Diff line change @@ -0,0 +1,104 @@ #include <omp.h> #include <stdlib.h> #include <stdio.h> #define MAX_N 26 #define X 0 #define Y 1 int N; int map[MAX_N][2]; // int position[MAX_N]; int ans[MAX_N] = {0}; int min_distance = 0; inline void print_solution(int position[]) { int i; int sum = 0; for (i = 1; i < N; i++){ int dx = map[position[i]][X] - map[position[i-1]][X]; int dy = map[position[i]][Y] - map[position[i-1]][Y]; sum += (dx * dx + dy * dy); } for (i = 0; i < N; i++){ printf("%d %d, ", map[position[i]][X], map[position[i]][Y]); } printf("sum: %d\n", sum); if(min_distance == 0){ min_distance = sum; }else if(sum < min_distance){ min_distance = sum; } } inline int ok(int position[], int next, int test) { int i; for (i = 0; i < next; i++) //if (position[i] == test || (abs(test - position[i]) == next - i)) if (position[i] == test) return 0; return 1; } void queen(int position[], int next, int row, int current_distance) { int test; if (next >= N) { //ans[row]++; //print_solution(position); #pragma omp critical { if(min_distance == 0){ min_distance = current_distance; }else if(current_distance < min_distance){ min_distance = current_distance; } } return; } //#pragma omp parallel for for (test = 0; test < N; test++) if (ok(position, next, test)) { position[next] = test; int dx = map[position[next]][X] - map[position[next-1]][X]; int dy = map[position[next]][Y] - map[position[next-1]][Y]; int added_distance = current_distance + (dx * dx + dy * dy); if(min_distance > 0 && added_distance > min_distance) continue; queen(position, next + 1, row, added_distance); } } int main(int argc, char *argv[]) { scanf("%d", &N); int i; for(i = 0; i < N; i++){ scanf("%d %d", &map[i][X], &map[i][Y]); } int position[MAX_N] = {0}; #pragma omp parallel for private(position) for(i = 0; i < N; i++){ position[0] = i; queen(position, 1, i, 0); } printf("%d\n", min_distance); return 0; }