Solve the Eight Queens Problem using backtracking - C Data Structure

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Description

Solve the Eight Queens Problem using backtracking

Demo Code

#include<stdio.h>
#include<math.h>

void queen(int row, int p);
int chess[8],count;

int main()/*from  w  w  w  .  j ava2 s.  c  o  m*/
{
     int p = 8;
     queen(1,p);
     return 0;
}

void print(int p)
{
     int i,j;
     printf("\n\nThis is Solution no. %d:\n\n",++count);
     for(i=1;i<=p;++i)
         printf("\t%d",i);
     
     for(i=1;i<=p;++i){
          printf("\n\n%d",i);
          for(j=1;j<=p;++j){
               if(chess[i]==j)
                    printf("\tQ");
               else
                    printf("\t-");
          }
     }
     printf("\n\n\nThere are total 92 solutions for 8-queens problem.");
}

int place(int row,int column)
{
     int i;
     for(i=1;i<=row-1;++i)
     {
          if(chess[i]==column)
               return 0;
          else
           if(abs(chess[i]-column)==abs(i-row))
                return 0;
     }
    
     return 1;
}

void queen(int row,int p)
{
     int column;
     for(column=1;column<=p;++column)
     {
          if(place(row,column))
          {
               chess[row]=column;
               if(row==p)
                    print(p);
               else
                    queen(row+1,p);
          }
     }
}

Result


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