fork download
copy 
  1. ////M queens N castles
  2. #include <stdio.h>
  3. void put(int row, int m, int n);
  4. int map[20][20]={0}, M, N;
  5. int num_solution = 0;
  6. int safeforqueen(int row,int col);
  7. int safeforcastle(int row, int col);
  8.  
  9. int main(void){
  10.     scanf("%d %d", &M, &N);
  11.     put(0, 0, 0);
  12.     printf("%d\n", num_solution);
  13.     return 0;
  14. }
  15.  
  16. void put(int row, int m, int n){
  17.     int col;
  18.     if(row == M+N){
  19.         num_solution ++;
  20.     }
  21.     else{
  22.         for(col = 0; col < M+N; col++){
  23.             if(m < M && safeforqueen(row, col)){
  24.                 map[row][col] = 1;
  25.                 put(row+1, m+1, n);
  26.                 map[row][col] = 0;
  27.             }
  28.  
  29.             if(n < N && safeforcastle(row, col)){
  30.                 map[row][col] = 2;
  31.                 put(row+1, m, n+1);
  32.                 map[row][col] = 0;
  33.             }
  34.         }
  35.     }
  36. }
  37.  
  38. int safeforqueen(int row, int col){
  39.     int r, c;
  40.     for(r= 0; r < row; r++){
  41.         if(map[r][col]) return 0;
  42.     }
  43.     for(r = row-1, c = col + 1; r >=0 && c < M+N; r--, c++){
  44.         if(map[r][c]) return 0;
  45.     }
  46.     for(r = row-1, c = col-1; r>= 0 && c >= 0; r--, c--){
  47.         if(map[r][c]) return 0;
  48.     }
  49.     return 1;
  50. }
  51.  
  52. int safeforcastle(int row, int col){
  53.     int r, c;
  54.     for(r= 0; r < row; r++){
  55.         if(map[r][col]) return 0;
  56.     }
  57.     for(r = row-1, c = col - 1; r >=0 && c>=0; r--, c--){
  58.         if(map[r][c]==1) return 0;
  59.     }
  60.     for(r = row-1, c = col+1; r>= 0 && c < M+N; r--, c++){
  61.         if(map[r][c]==1) return 0;
  62.     }
  63.     return 1;
  64. }
Success #stdin #stdout 0s 9432KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
1
https://ideone.com/HnDRk6
M queens N castles
language:
C (gcc 8.3)
created:
7 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!