oj.uz

답안 #696239

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
696239 2023-02-06T04:03:32 Z bachhoangxuan Mag (COCI16_mag) C++17
120 / 120
 453 ms 180872 KB 
// Judges with GCC >= 12 only needs Ofast
// #pragma GCC optimize("O3,no-stack-protector,fast-math,unroll-loops,tree-vectorize")
// MLE optimization
// #pragma GCC optimize("conserve-stack")
// Old judges
// #pragma GCC target("sse4.2,popcnt,lzcnt,abm,mmx,fma,bmi,bmi2")
// New judges. Test with assert(__builtin_cpu_supports("avx2"));
// #pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma,tune=native")
// Atcoder
// #pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma")
#include<bits/stdc++.h>
using namespace std;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
uniform_real_distribution<> pp(0.0,1.0);
#define int long long
#define ld long double
#define pii pair<int,int>
#define piii pair<int,pii>
#define fi first
#define se second
const int inf=1e18;
const int mod=998244353;
const int mod2=1e9+7;
const int maxn=1000005;
const int maxq=500005;
const int maxl=20;
const int maxa=1000005;
int power(int a,int n){
    int res=1;
    while(n){
        if(n&1) res=res*a%mod;
        a=a*a%mod;n>>=1;
    }
    return res;
}
int dep[maxn],c[maxn],n,ans,p,q;
vector<int> edge[maxn];
void dfs(int u,int par){
    int Max1=0,Max2=0;
    if(c[u]==1) dep[u]=1;
    for(int v:edge[u]){
        if(v==par) continue;
        dfs(v,u);
        if(c[u]==1){
            dep[u]=max(dep[u],dep[v]+1);
            if(dep[v]>Max1){Max2=Max1;Max1=dep[v];}
            else if(dep[v]>Max2) Max2=dep[v];
        }
    }
    if(c[u]==1){
        ans=max(ans,dep[u]);
        ans=max(ans,Max1+Max2+1);
    }
}
void redfs(int u,int par,int len){
    int Max1=0,Max2=0;
    for(int v:edge[u]){
        if(v==par) continue;
        if(dep[v]>Max1){Max2=Max1;Max1=dep[v];}
        else if(dep[v]>Max2) Max2=dep[v];
    }
    if(len>Max1){Max2=Max1;Max1=len;}
    else if(len>Max2) Max2=len;
    if(p==0 && q==0){p=c[u];q=Max1+Max2+1;}
    else if(c[u]*q<(Max1+Max2+1)*p){p=c[u];q=Max1+Max2+1;}
    for(int v:edge[u]){
        if(v==par) continue;
        if(c[u]!=1) redfs(v,u,0);
        else redfs(v,u,max(len,(dep[v]==Max1?Max2:Max1))+1);
    }
}
void solve(){
    cin >> n;
    for(int i=1;i<n;i++){
        int u,v;cin >> u >> v;
        edge[u].push_back(v);
        edge[v].push_back(u);
    }
    for(int i=1;i<=n;i++) cin >> c[i];
    dfs(1,0);redfs(1,0,0);
    if(ans!=0 && q<p*ans){p=1;q=ans;}
    int g=__gcd(p,q);p/=g;q/=g;
    cout << p << '/' << q << '\n';
}
signed main(){
    //freopen("TREE.INP","r",stdin);
    //freopen("TREE.OUT","w",stdout);
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);cout.tie(NULL);
    int test=1;//cin >> test;
    while(test--) solve();
}

Subtask #1
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Correct 12 ms 23764 KB Output is correct

Subtask #2
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 12 ms 23832 KB Output is correct
2 Correct 13 ms 23776 KB Output is correct

Subtask #3
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 323 ms 105084 KB Output is correct

Subtask #4
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 11 ms 23764 KB Output is correct
2 Correct 444 ms 178968 KB Output is correct

Subtask #5
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 422 ms 176836 KB Output is correct

Subtask #6
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 316 ms 70632 KB Output is correct
2 Correct 221 ms 58444 KB Output is correct

Subtask #7
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 334 ms 72928 KB Output is correct
2 Correct 62 ms 29116 KB Output is correct
3 Correct 453 ms 180872 KB Output is correct

Subtask #8
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 69 ms 29244 KB Output is correct
2 Correct 337 ms 86632 KB Output is correct
3 Correct 281 ms 57936 KB Output is correct

Subtask #9
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 322 ms 68752 KB Output is correct
2 Correct 327 ms 70112 KB Output is correct

Subtask #10
12.0 / 12.0

# 결과 실행 시간 메모리 Grader output
1 Correct 310 ms 71612 KB Output is correct
2 Correct 268 ms 50400 KB Output is correct