Submission #1234066

#	Time	Username	Problem	Language	Result	Execution time	Memory
1234066		Geforgs	Hotspot (NOI17_hotspot)	C++20	100 / 100	550 ms	1400 KiB

hotspot

#include <iostream>
#include <iomanip>
#include <vector>
#include <cmath>
#include <algorithm>
#include <set>
#include <queue>
#include <map>
#include <unordered_map>
#include <stack>
#include <bitset>
#include <string>
#include <cstring>
#include <iterator>
#include <random>
#define ll long long
#define ld long double
#define inf (ll)(2*1e18)
#define sort(a) sort(a.begin(), a.end())
#define reverse(a) reverse(a.begin(), a.end())
#define pb push_back
#define endl "\n"
using namespace std;

void find(ll n, ll x, ll y, vector<vector<ll>>& a, vector<ld>& ans){
    vector<ll> dis1(n, -1);
    vector<ll> dis2(n, -1);
    vector<ll> cnt1(n, 0);
    vector<ll> cnt2(n, 0);
    queue<ll> que;
    dis1[x] = 0;
    cnt1[x] = 1;
    que.push(x);
    while(!que.empty()){
        auto z = que.front();
        que.pop();
        for(auto el: a[z]){
            if(dis1[el] == -1){
                dis1[el] = dis1[z] + 1;
                que.push(el);
            }
            if(dis1[el] == dis1[z] + 1){
                cnt1[el] += cnt1[z];
            }
        }
    }
    dis2[y] = 0;
    cnt2[y] = 1;
    que.push(y);
    while(!que.empty()){
        auto z = que.front();
        que.pop();
        for(auto el: a[z]){
            if(dis2[el] == -1){
                dis2[el] = dis2[z] + 1;
                que.push(el);
            }
            if(dis2[el] == dis2[z] + 1){
                cnt2[el] += cnt2[z];
            }
        }
    }
    ll dis = dis1[y], cnt=cnt1[y];
    for(int i=0;i<n;++i){
        if(dis1[i] + dis2[i] == dis){
            ans[i] += (ld)(cnt1[i]*cnt2[i])/(ld)cnt;
        }
    }
}

void solve(){
    ll n, m, k, i, x, y, answer=0;
    ld res=0;
    cin>>n>>m;
    vector<vector<ll>> a(n);
    vector<ld> ans(n);
    for(i=0;i<m;++i){
        cin>>x>>y;
        a[x].pb(y);
        a[y].pb(x);
    }
    cin>>k;
    for(i=0;i<k;++i){
        cin>>x>>y;
        find(n, x, y, a, ans);
    }
    for(i=0;i<n;++i){
        if(ans[i] > res){
            res = ans[i];
            answer = i;
        }
    }
    cout<<answer<<endl;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    srand(time(nullptr));
    ll t=1;
//    cin>>t;
    for(;t>0;--t){
        solve();
    }
    return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 5 / 5
• Subtask 3: 11 / 11
• Subtask 4: 18 / 18
• Subtask 5: 26 / 26
• Subtask 6: 36 / 36