八皇后问题

#include

#include

#include

#define N 8

int left[2*N+1];

int right[2*N+1];

int column[N+1];

int a[N+1];

int times=0;

void show(){

times++;

printf("第%d个\n",times);

int i,j;

for(i=1;i<=N;i++){

for(j=1;j<=N;j++){

          if(a[i]==j)

printf("1 ");

else

printf(".");

}

printf("\n");

    }

printf("\n");

}

void search(int row){

if(row>N)

show();

else{

int col;

for(col=1;col<=N;col++){

//printf("column[%d]:%d\n",col,column[col]);

if(column[col]==0&&left[N+row-col]==0&&right[col+row]==0){

column[col]=1;

left[N+row-col]=1;

right[row+col]=1;

a[row]=col;

search(row+1);

column[col]=0;

   left[N+row-col]=0;

right[row+col]=0;

}

}

}

}

int main(){

memset(left,0,2*N+1);

memset(right,0,2*N+1);

memset(column,0,N+1);

memset(a,-1,N+1);

search(1);

return 0;

}