Submission #828552

# Submission time Handle Problem Language Result Execution time Memory
828552 2023-08-17T11:02:25 Z TB_ Network (BOI15_net) C++17
0 / 100
1 ms 324 KB
#include <bits/stdc++.h>
using namespace std;

// #undef _GLIBCXX_DEBUG                // disable run-time bound checking, etc
// #pragma GCC optimize("Ofast,inline") // Ofast = O3,fast-math,allow-store-data-races,no-protect-parens
// #pragma GCC optimize ("unroll-loops")

// #pragma GCC target("bmi,bmi2,lzcnt,popcnt")                      // bit manipulation
// #pragma GCC target("movbe")                                      // byte swap
// #pragma GCC target("aes,pclmul,rdrnd")                           // encryption
// #pragma GCC target("avx,avx2,f16c,fma,sse3,ssse3,sse4.1,sse4.2") // SIMD

// #include <bits/extc++.h>
// using namespace __gnu_pbds;
// template<class T>using ordered_set = tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update>;
// template<class T>using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag,tree_order_statistics_node_update>;

#define ll long long
#define INF (ll)1e9+7
#define fo(i, n) for(ll i=0;i<((ll)n);i++)
#define deb(x) cout << #x << " = " << x << endl;
#define deb2(x, y) cout << #x << " = " << x << ", " << #y << " = " << y << endl
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define LSOne(S) ((S) & (-S))
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
inline int readint(){ int v = 0; char c; while((c = getchar()) != EOF && c != ' ' && c != '\n'){ v *= 10; v += c - '0'; } return v; }
inline int readintsigned() { int v = 0; int sign = 1; char c = getchar(); if (c == '-') { sign = -1; } else { v += c - '0'; } while ((c = getchar()) != EOF && c != ' ' && c != '\n') { v *= 10; v += c - '0'; } return v * sign; }
inline string readstring() { string s; char c; while ((c = getchar()) != EOF && c != '\n' && c != ' ') { s.push_back(c); } return s; }
template <class result_t=std::chrono::milliseconds,class clock_t=std::chrono::steady_clock,class duration_t = std::chrono::milliseconds>
auto since(std::chrono::time_point<clock_t, duration_t> const& start){return std::chrono::duration_cast<result_t>(clock_t::now() - start);}
typedef pair<int, int> pii;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<pii> vpii;
typedef vector<pl> vpl;
typedef vector<vi> vvi;
typedef vector<vl> vvl;
typedef vector<vpii> vvpii;
typedef vector<vpl> vvpl;



int main() {
    // cout << fixed << setprecision(20);
    // auto start = std::chrono::steady_clock::now(); // since(start).count()
    cin.tie(0)->sync_with_stdio(0);

    int n, from, to;
    cin >> n;
    vi degree(n, 0);
    fo(i, n-1){
        cin >> from >> to;
        degree[from-1]++;
        degree[to-1]++;
    }
    vi leaf;
    fo(i, n) if(degree[i] == 1) leaf.pb(i);
    if(((ll)leaf.size())%2 == 1){
        leaf.pb((leaf[leaf.size()-1] == 1?0:1));
    }
    cout << leaf.size()/2 << "\n";
    for(int i = 0; i<leaf.size(); i+=2) cout << leaf[i]+1 << " " << leaf[i+1]+1 << "\n";


    return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:67:21: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   67 |     for(int i = 0; i<leaf.size(); i+=2) cout << leaf[i]+1 << " " << leaf[i+1]+1 << "\n";
      |                    ~^~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 324 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Incorrect 0 ms 212 KB Breaking single line is causing network to disconnect.
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 324 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Incorrect 0 ms 212 KB Breaking single line is causing network to disconnect.
5 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 0 ms 324 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Incorrect 0 ms 212 KB Breaking single line is causing network to disconnect.
5 Halted 0 ms 0 KB -