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ID	题目	提交者	结果	用时	内存	语言	文件大小	提交时间	测评时间
#758726	#5307. Subgraph Isomorphism	einekleine18	WA	59ms	3648kb	C++20	2.5kb	2024-11-17 19:29:52	2024-11-17 19:29:52

Judging History

你现在查看的是最新测评结果

[2024-11-17 19:29:52]
评测

测评结果：WA
用时：59ms
内存：3648kb

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[2024-11-17 19:29:52]
提交

answer

#include<bits/stdc++.h>

#ifdef DEBUG
#include "debug.h"
#else
#define debug(...) 42
#endif

#define int long long
typedef unsigned long long ull;
const ull mask = std::chrono::steady_clock::now().time_since_epoch().count();
void solve(){
    int n,m;
    std::cin>>n>>m;
    std::vector g(n,std::vector<int>());
    std::vector<int>du(n);
    for(int i=0;i<m;++i){
        int a,b;
        std::cin>>a>>b;
        --a,--b;
        g[a].push_back(b);
        g[b].push_back(a);
        ++du[a];
        ++du[b];
    }
    if(m==n-1){
        std::cout<<"YES\n";
        return;
    }
    if(m>n){
        std::cout<<"NO\n";
        return;
    }
    std::queue<int>q;
    std::vector<int>st(n);
    int sz=n;
    for(int i=0;i<n;++i){
        if(du[i]==1){
            q.push(i);
        }
    }
    while(!q.empty()){
        int t=q.front();q.pop();
        st[t]=1;
        --sz;
        for(auto &x:g[t]){
            if(--du[x]==1){
                q.push(x);
            }
        }
    }
    auto shift=[&](ull x)->ull {
        x^=mask;
        x^=x<<13;
        x^=x>>7;
        x^=x<<17;
        x^=mask;
        return x;
    };
    auto hash=[&](auto self,int u,int fa)->ull {
        ull res=1;
        for(auto &x:g[u]){
            if(x==fa||!st[x]) continue;
            ull son=self(self,x,u);
            res+=shift(son);
        }
        return res;
    };
    std::vector<ull>tr;
    int root=-1;
    for(int i=0;i<n;++i){
        if(!st[i]){
            root=i;
            break;
        }
    }
    int last=-1;
    for(int i=0;i<sz;++i){
        tr.push_back(hash(hash,root,-1));
        for(auto &x:g[root]){
            if(x!=last){
                last=root;
                root=x;
                break;
            }
        }
    }
    sz=tr.size();
    for(int i=0;i<sz;++i){
        if(tr[i]!=tr[(i+2)%sz]){
            std::cout<<"NO\n";
            return;
        }
    }
    std::cout<<"YES\n";
}
signed main(){
    // freopen("in.txt","r",stdin);freopen("out.txt","w",stdout);
    // std::cout<<std::fixed<<std::setprecision(12);
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);std::cout.tie(nullptr);
    int _=1;
    std::cin>>_;
    // clock_t start=clock();
    for(int i=1;i<=_;++i){
        solve();
    }
    // clock_t end=clock();
    // double time=static_cast<double>(end-start)/CLOCKS_PER_SEC;
    // std::cout<<time<<'\n';
    return 0;
}

源文件, 语言: C++20

详细

Test #1:

score: 100

Accepted

time: 0ms

memory: 3628kb

input:

output:

YES
YES
NO
YES

result:

ok 4 token(s): yes count is 3, no count is 1

Test #2:

score: -100

Wrong Answer

time: 59ms

memory: 3648kb

input:

output:

YES
YES
YES
YES
YES
NO
YES
NO
NO
YES
YES
NO
NO
NO
NO
NO
NO
YES
NO
NO
NO
NO
YES
NO
NO
NO
NO
NO
NO
NO
YES
YES
NO
YES
YES
NO
NO
NO
YES
NO
NO
NO
NO
NO
YES
NO
NO
NO
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
...

result:

wrong answer expected YES, found NO [60th token]