我废了

lucy2012 @ 2024-05-02 21:19:12

#include<bits/stdc++.h>
using namespace std;
int n,sum=0,d1[110],d2[110],d3[30],a[30];
void dfs(int x){
    if(x>n){
        sum++;
        if(sum<=3){
            for(int i=1;i<=n;i++)
                cout<<a[i]<<' ';
            cout<<endl;
        }
        return; 
    }
    for(int i=1;i<=n;i++){
        if(d3[i]==0&&d1[x+i]==0&&d2[x-i+15]==0){
            a[x]=i;
            d3[i]=1;d1[x+i]=1;d2[x-i+15]=1;
            dfs(x+1);
            d3[i]=0;d1[x+i]=0;d2[x-i+15]=0;
        }
    }
}
int main() {
    cin>>n;
    dfs(1);
    cout<<sum;
    return 0;
}

by I_Love_DS @ 2024-05-02 21:46:42

脑子里只有白色

by smile_jyc @ 2024-05-02 21:47:39

@lucy2012 枚举子集

#include<bits/stdc++.h>
using namespace std;
long long rol[1000],col[1000],u[1000],v[1000];//行列 
long long n,cnt=0;
long long  dfs(long long cur){
    if(cur>n){
        if(cnt<=2){
            for(int i=1;i<=n;i++){
                cout<<rol[i]<<" ";;
            }
            cout<<endl;
        }
        cnt++;
        return 0;
    }
    for(long long i=1;i<=n;i++){
        if((!col[i])&&(!u[cur+i])&&(!v[cur-i+n])){
            rol[cur]=i;
            col[i]=1;
            u[cur+i]=1;
            v[cur-i+n]=1;
            dfs(cur+1);
            col[i]=0;
            u[cur+i]=0;
            v[cur-i+n]=0;

        } 
    }
}
int main(){
    cin>>n;
    dfs(1);
    cout<<cnt;

    return 0;
}

by lucy2012 @ 2024-05-02 21:55:51

@hhhcj @liuruiqing @smile_jyc 告诉大家一个好消息，我是正常人，终于懂了！！！（皆大欢喜

by lucy2012 @ 2024-05-02 21:57:21

开心(*^▽^*)

by I_Love_DS @ 2024-05-03 16:38:41

亦开心也！

by lucy2012 @ 2024-05-03 16:55:25

理解完就写了篇题解QwQ