八皇后问题之回溯法

#include <math.h>
#include <stdio.h>
#include <string.h>
#include <algorithm>
#include <iostream>
using namespace std;

#define N 20

int n, sum, x[N+1];            // n:问题规模 sum:方案数目 x[]方案存储

void Init()
{
    cout << "输入皇后问题规模：";
    cin >> n; sum = 0;
    memset(x, 0, sizeof(x));
}
bool check(int row)
{
    for(int i = 1; i < row; i++)
    {
        if(x[i]==x[row] || abs(x[row]-x[i])==abs(row-i))
            return false;
    }
    return true;
}
void PrintResult()
{
    cout << "方案" << ++sum << ":" << endl;
    for(int i = 1; i <= n; i++)
    {
        cout << x[i];
        cout << (i==n) ? "
" : " ";
    }
}
void Process(int row)
{
    if(row > n)
        PrintResult();
    for(int i = 1; i <= n; i++)
    {
        x[row] = i;
        if(check(row))
            Process(row+1);
    }
}
int main()
{
    Init();
    Process(1);
    return 0;
}