C :

#include<stdio.h>
#include<stdlib.h>
int a[10];
void output(int n)
{
	int i;
	for(i=1;i<=n;i++)
		printf("%d",a[i]);
	printf("\n");
}
int check(int k)
{
	int i;
	for(i=1;i<=k-1;i++)
		if((abs(a[i]-a[k])==abs(i-k))||a[i]==a[k])
			return 0;
		return 1;
}
void backdate(int n)
{
	int k=1;
	a[1]=0;
	while(k>0)
	{
		a[k]=a[k]+1;
		while(a[k]<=n&&check(k)==0)
			a[k]=a[k]+1;
		if(a[k]<=n)
        {
			if(k==n)
				output(n);
			else
			{
				k=k+1;
				a[k]=0;
			}
		}
		else
			k=k-1;
	}
}
int main()
{
	backdate(8);
	return 0;
}

C++ :

#include<iostream>
#include<cstring>
#include<cstdio>
using namespace std;

int r, a, b; int count = 0, ans = 0;

void dfs( int row ) {
    if( row == 8 ) { count++; cout<<ans<<endl; return; }
    for( int i = 0; i < 8; ++i ) {
        if( !(r&(1<<i)) && !(a&(1<<(row+i))) && !(b&(1<<(row-i+7))) ) {
           r |= (1<<i); a |= (1<<(row+i)); b |= (1<<(row-i+7));
           ans = ans * 10 + (i+1);
           dfs(row+1);
           ans /= 10;
           r &= ~(1<<i); a &= ~(1<<(row+i)); b &= ~(1<<(row-i+7));
        }
    }
}

int main(){
    //freopen("out.txt", "w", stdout);
    dfs(0); //cout<<"一共有"<<count<<"种方法！";
    return 0;
}