87pts WA最后一个点aaa

peterJr @ 2024-03-27 19:26:27

#include <cstdio>

using namespace std;

int n, col[17], dia1[17], dia2[17], a[17], tot;

inline int print()
{
    if (++tot > 3) return EOF;

    for (int i = 1; i <= n; ++i)
        cout << a[i] << " "; 
    cout << endl;

    return 0;
}

void dfs(int k)
{
    if (k > n) 
    {
        print();
    }

    for (int i = 1; i <= n; ++i)
    {
        if (!col[i] && !dia1[k + i] && !dia2[k - i + n])
        {
            col[i] = 1;
            dia1[k + i] = 1;
            dia2[k - i + n] = 1;

            a[k] = i;
            dfs(k + 1);
            a[k] = 0;

            col[i] = 0;
            dia1[k + i] = 0;
            dia2[k - i + n] = 0;
        }
    }
}

int main()
{
    cin >> n;

    dfs(1);

    cout << tot << endl;

    return 0;
}

by peterJr @ 2024-03-27 19:40:35

用 dfs 怎么错了？？？

by jydz @ 2024-04-08 13:29:32

@peterJr

#include<bits/stdc++.h>
using namespace std;

int n;
bool v[15];
int a[15];
bool b[30],c[30];
int ans=0;

void dfs(int x)
{
    if (x>n)
    {
        ans++;
        if (ans<=3)
        {
            for (int i=1;i<=n;i++)
                cout<<a[i]<<" ";
            cout<<endl; 
        }
    }
    else
    {
        for (int i=1;i<=n;i++)
        {
            if (v[i] && b[i+x] && c[i-x+n])
            {
                a[x]=i;
                v[i]=false;
                b[i+x]=false;
                c[i-x+n]=false;
                dfs(x+1);
                v[i]=true;
                b[i+x]=true;
                c[i-x+n]=true;  
            }
        }
    }
}

int main()
{
    cin>>n;
    memset(v,true,sizeof(v));
    memset(a,0,sizeof(a));
    memset(b,true,sizeof(b));
    memset(c,true,sizeof(c));           
    dfs(1);
    cout<<ans;
    return 0;
}