Submission #382068

#	Time	Username	Problem	Language	Result	Execution time	Memory
382068		Aryan_Raina	Network (BOI15_net)	C++14	0 / 100	1 ms	492 KiB

net

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define ld long double
#define ar array

const int INF = 1e17;
const int MOD = 1e9 + 7;

const int MXN = 5e5+9;
int cnt[MXN];
int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n; cin>>n;
    for (int i = 0; i < n-1; i++) {
        int a, b; cin>>a>>b; --a, --b;
        cnt[a]++, cnt[b]++;
    }
    vector<int> outer;
    for (int i = 0; i < n; i++) if (cnt[i] == 1) outer.push_back(i+1);
    cout<<(outer.size()+1)/2<<"\n";
    for (int i = 1; i < outer.size(); i+=2) {
        cout<<outer[i]<<" "<<outer[i-1]<<"\n";
    } 
    if (outer.size() % 2 == 1) cout<<outer.back()<<" 1\n";
} 

Compilation message (stderr)

net.cpp: In function 'int32_t main()':
net.cpp:24:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   24 |     for (int i = 1; i < outer.size(); i+=2) {
      |                     ~~^~~~~~~~~~~~~~

• Subtask 1: 0 / 18
• Subtask 2: 0 / 45
• Subtask 3: 0 / 37