Submission #361968

#	Time	Username	Problem	Language	Result	Execution time	Memory
361968		Sparky_09	Traffic (IOI10_traffic)	C++17	100 / 100	1191 ms	159032 KiB

traffic

#include "traffic.h"
#include <bits/stdc++.h>
using namespace std;
#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<ll, ll> pii;
typedef vector<ll> vi;
typedef vector<pii> vpi;

void usaco(string s){
  freopen((s+".in").c_str(), "r", stdin);
  freopen((s+".out").c_str(), "w", stdout);
}

const int MX = 1e6;
const int INF = 2e9 + 1;

int fans = 0;

vector<int> g[MX], nodes(MX), people(MX), children(MX);

void dfs (int v, int parent) {
    for (auto x: g[v]) {
        if (x == parent) continue;
        dfs(x, v);
        children[v] += children[x];
        people[v] = max(people[v], children[x]);
    }
    people[v] = max(people[v], fans - children[v] - nodes[v]);
    children[v] += nodes[v];
}

int LocateCentre (int n, int p[], int d[], int s[]) {
    for (int i = 0; i < n; i++) {
        fans += p[i];
        nodes[i] = p[i];
    }
    for (int i = 0; i < n - 1; i++) {
        g[s[i]].push_back(d[i]);
        g[d[i]].push_back(s[i]);
    }
    dfs(0, -1);
    int sol = INF, res = -1;
    for (int i = 0; i < n; i++) {
        if (people[i] < sol) {
            res = i;
            sol = people[i];
        }
    }
    return res;
}

/*
int main() {
	cin.tie(0)->sync_with_stdio(0);
	cin.exceptions(cin.failbit);
#ifdef LOCAL_DEFINE
	freopen("input.txt", "r", stdin);
#endif

}
*/

Compilation message (stderr)

traffic.cpp: In function 'void usaco(std::string)':
traffic.cpp:13:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   13 |   freopen((s+".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
traffic.cpp:14:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   14 |   freopen((s+".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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