Submission #385205

#	Time	Username	Problem	Language	Result	Execution time	Memory
385205		vishesh312	Traffic (IOI10_traffic)	C++17	100 / 100	1167 ms	139756 KiB

traffic

#include "bits/stdc++.h"
#include "traffic.h"
using namespace std;
/*
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using ordered_set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
*/

#define all(x) begin(x), end(x)
#define sz(x) (int)x.size()

using ll = long long;
const int mod = 1e9+7;

vector<int> sub, par;
vector<vector<int>> adj;

void dfs(int u, int p = -1) {
    par[u] = p;
    for (int v : adj[u]) {
        if (v != p) {
            dfs(v, u);
        }
    }
    for (int v : adj[u]) {
        if (v != p) {
            sub[u] += sub[v];
        }
    }
}

int LocateCentre(int n, int v[], int U[], int V[]) {
    sub = vector<int>(v, v+n);
    par.resize(n); adj.resize(n);
    for (int i = 0; i < n-1; ++i) {
        adj[U[i]].push_back(V[i]);
        adj[V[i]].push_back(U[i]);
    }
    dfs(0);
    int ans, mx = 2e9+5;
    for (int i = 0; i < n; ++i) {
        int cur = sub[0] - sub[i];
        for (int v : adj[i]) {
            if (v != par[i]) {
                cur = max(cur, sub[v]);
            }
        }
        if (cur < mx) {
            mx = cur;
            ans = i;
        }
    }
    return ans;
}

Compilation message (stderr)

traffic.cpp: In function 'int LocateCentre(int, int*, int*, int*)':
traffic.cpp:54:12: warning: 'ans' may be used uninitialized in this function [-Wmaybe-uninitialized]
   54 |     return ans;
      |            ^~~

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