HDOJ_ACM_N皇后问题

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#include <stdio.h>
#include <math.h>
#include <stdlib.h>
int q[11];  //q[1] means the coordinate of queue is (1, q[1])
int result[11];//to save the time, so record the previous time
int n;
int check(int k) //check if the kth queen is conflict with previous ones
{
int i;
i = 1;
while (i < k)
{
//k - i == abs(q[k] - q[i]) means the current queen is not 45° with other queens
if (q[i] == q[k] || k - i == abs(q[k] - q[i]))
return 0;
i++;
}
return 1;
}
int count;  //record the count of rank
int flag;
void DFS(int step)
{
int i, j, k;
if (step == n + 1)
count++;
else
{
for (i = 1; i <= n; i++)
{
q[step] = i;
if (check(step) == 0)
continue;
DFS(step + 1);
}
}
}
int main()
{
while (scanf("%d", &n) != EOF && n)
{
//memset();
count = 0;
if (result
== 0)
{
DFS(1);
result
= count;
}
printf("%d\n", result
);
}
return 0;
}