样例过了，全部WA，求助

wozhenbanghahei @ 2023-04-29 11:44:35

#include<bits/stdc++.h>
using namespace std;
int n,ans;
int a[105],book[105],c[105],d[105];
void dfs(int step)
{
    if(step>n)
    {
        ans++;
        if(ans<=3)
        {
            for(int i=1;i<n;i++) cout<<a[i];
            cout<<a[n]<<endl;
        }
        return;
    }
    for(int i=1;i<=n;i++)
    {
        if(!book[i] && !c[i+step] && !d[i-step+n])
        {
            book[i]=1;
            c[i+step]=1;
            d[i-step+n]=1;
            a[step]=i;
            dfs(step+1);
            book[i]=0;
            c[i+step]=0;
            d[i-step+n]=0;
        }
    }
    return;
} 
int main()
{
    cin>>n;
    dfs(1);
    cout<<ans;
    return 0;
}

by XEZ323 @ 2023-05-19 17:16:06

忘记打出空格了，看一下样例。

#include<bits/stdc++.h>
using namespace std;
int n,ans;
int a[105],book[105],c[105],d[105];
void dfs(int step)
{
    if(step>n)
    {
        ans++;
        if(ans<=3)
        {
            for(int i=1;i<n;i++) cout<<a[i]<<" ";
            cout<<a[n]<<endl;
        }
        return;
    }
    for(int i=1;i<=n;i++)
    {
        if(!book[i] && !c[i+step] && !d[i-step+n])
        {
            book[i]=1;
            c[i+step]=1;
            d[i-step+n]=1;
            a[step]=i;
            dfs(step+1);
            book[i]=0;
            c[i+step]=0;
            d[i-step+n]=0;
        }
    }
    return;
} 
int main()
{
    cin>>n;
    dfs(1);
    cout<<ans;
    return 0;
}

这样应该就可以了。实测AC