Submission #958150

#	Time	Username	Problem	Language	Result	Execution time	Memory
958150		vjudge1	Traffic (IOI10_traffic)	C++17	100 / 100	1000 ms	164688 KiB

traffic

#include <bits/stdc++.h>
#include <traffic.h>
using namespace std;
using ll = long long;
 
//#define int long long
#define FOR(i, a, b) for (int i = a; i <= b; i++)
#define FORD(i, a, b) for (int i = b; i >= a; i --)
#define REP(i, n) for (int i = 0; i < n; ++i)
#define REPD(i, n) for (int i = n - 1; i >= 0; --i)
 
#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)
 
constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
void setupIO(){
    #define name "Whisper"
    //Phu Trong from Nguyen Tat Thanh High School for gifted student
    srand(time(NULL));
    cin.tie(nullptr)->sync_with_stdio(false); cout.tie(nullptr);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    cout << fixed << setprecision(10);
}
 
template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-9;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }
 
template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-9;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
const int MAX = 1e6 + 5;
vector<int> G[MAX];
int numNode;
int p[MAX], s[MAX], d[MAX];
ll dp[MAX], sz[MAX];
void dfs_down(int u, int pa = -1){
    sz[u] = p[u];
    for (int &v : G[u]) if(v ^ pa){
        dfs_down(v, u);
        sz[u] += sz[v];
        maximize(dp[u], sz[v]);
    }
}
void dfs_up(int u, int pa = -1){
    for(int &v : G[u]) if(v ^ pa){
        dfs_up(v, u);
    }
    maximize(dp[u], sz[0] - sz[u]);
}
int LocateCentre(int _n, int P[], int S[], int D[]){
    numNode = _n;
    for (int i = 0; i < numNode; ++i){
        p[i] = P[i];
        s[i] = S[i];
        d[i] = D[i];
    }
 
    for (int i = 0; i < numNode - 1; ++i){
        G[s[i]].emplace_back(d[i]);
        G[d[i]].emplace_back(s[i]);
    }
    dfs_down(0);
    dfs_up(0);
    int ans = 0;
    for (int i = 1; i < numNode; ++i){
        if (dp[i] < dp[ans]){
            ans = i;
        }
    }
    return ans;
}
//int P[MAX], S[MAX], D[MAX];
//void Whisper(){
//    cin >> numNode;
//    for (int i = 0; i < numNode; ++i) cin >> P[i];
//    for (int i = 0; i < numNode - 1; ++i){
//        cin >> S[i] >> D[i];
//    }
//    cout << LocateCentre(numNode, P, S, D);
//}
 
 
//signed main(){
//    setupIO();
//    int Test = 1;
////    cin >> Test;
//    for ( int i = 1 ; i <= Test ; i++ ){
//        Whisper();
//        if (i < Test) cout << '\n';
//    }
//}
 
 

• Subtask 1: 25 / 25
• Subtask 2: 25 / 25
• Subtask 3: 25 / 25
• Subtask 4: 25 / 25