算法高手请进

用排列树算法解N后问题，C++编程

#include <stdio.h>
#include <stdlib.h>

const int N=20;
int q[N];
int cont=0;

void print(int n)
{
cont++;
int i;
printf("第%d个解:",cont);
for(i=1;i<=n;i++)
printf("%d",q[i]);
printf("\n");
}

int find(int i,int k)
{
int j;
j=1;
while(j<k)
{
if((q[j]==i)||(abs(q[j]-i)==abs(j-k)))
return 0;
j++;
}
return 1;
}

void place(int k,int n)
{
if(k>n)
print(n);
else
for(int i=1;i<=n;i++)
if(find(i,k))
{
q[k]=i;
place(k+1,n);
}
}

void main()
{
int n;
printf("皇后问题(n<20) n=");
scanf("%d",&n);
printf("%d皇后问题求解如下:\n",n);
place(1,n);
printf("\n");
}

# include <stdio.h> # include <stdlib.h> # define MAXN 20 int n,m,good; int col[MAXN+1],a[MAXN+1]; int b[2*MAXN+1],c[2*MAXN+1]; int main() {int j; char awn; printf("输入n:");scanf("%d",&n); for(j=0;j<=n;j++)a[j]=1; for(j=0;j<=2*n;j++)b[j]=c[j]=1; m=1;col[1]=1;good=1;col[0]=0; do{ if (good) if (m==n) { printf("列\t\t行\n"); for (j=1;j<=n;j++) printf("%3d\t%d\n",j,col[j]); scanf("%c",&awn); if (awn=='Q'||awn=='q') exit(0); while (col[m]==n) { m--; a[col[m]]=b[m+col[m]]=c[n+m-col[m]]=1; } col[m]++; } else { a[col[m]]=b[m+col[m]]=c[n+m-col[m]]=0; col[++m]=1; } else { while (col[m]==n){ m--; a[col[m]]=b[m+col[m]]=c[n+m-col[m]]=1; } col[m]++; } good=a[col[m]]&&b[m+col[m]]&&c[n+m-col[m]]; }while (m!=0); }