Submission #468128

#	Time	Username	Problem	Language	Result	Execution time	Memory
468128		MohamedFaresNebili	Senior Postmen (BOI14_postmen)	C++14	100 / 100	463 ms	73176 KiB

postmen

#include <bits/stdc++.h>
 
using namespace std;
 
using ll  = long long;
using ld  = long double;
using db  = double;
using ii  = pair<int, int>;
using pl  = pair<ll, ll>;
using vi  = vector<int>;
using vl  = vector<ll>;
using vii = vector<ii>;
using vpl = vector<pl>;
 
#define mp make_pair
#define pb push_back
#define pp pop_back
#define ff first
#define ss second
#define lb lower_bound
#define ub upper_bound
#define all(x) (x).begin() , (x).end()
 
ld dist(ld x, ld y, ld a, ld b)    { return sqrt((x-a)*(x-a) + (y-b)*(y-b)); }
ll gcd(ll a , ll b){ return b ? gcd(b , a % b) : a ;}
ll lcm(ll a , ll b){ return (a * b) / gcd(a , b);}
ll fact(ll n) { return n > 1?(n * fact(n-1)):1;}
 
const int MOD = 1000*1000*1000+7;
const long double EPS = 0.000000001;
const double PI = 3.14159265358979323846;
const long long INF = 1e18;
const int nx[4] = {0, 0, -1, 1}, ny[4] = {1, -1, 0, 0};
 
int n, m; vector<ii>adj[500024];
bool queued[500024], vis[500024]; int cnt[500024];
int dfs(int v, int p=-1)
{
    if(queued[v]) {
        cout<<v+1<<" ";
        return v;
    }
    queued[v]=1;
    for(;cnt[v]<adj[v].size();cnt[v]++) {
      	ii u=adj[v][cnt[v]];
        if(u.ff==p||vis[u.ss]) continue;
        vis[u.ss]=true; int next=dfs(u.ff, v);
        if(next!=v) {
            queued[v]=0;
            cout<<v+1<<" ";
            return next;
        }
        cout<<"\n";
    }
    return -1;
}
 
int32_t main()
{
    ios::sync_with_stdio(0); cin.tie(0);cout.tie(0);
    cin>>n>>m;
    for(int l=0;l<m;l++) {
        int a, b; cin>>a>>b; a--; b--;
        adj[a].pb({b, l}); adj[b].pb({a, l});
    }
    for(int l=0;l<n;l++) dfs(l);
    return 0;
}

Compilation message (stderr)

postmen.cpp: In function 'int dfs(int, int)':
postmen.cpp:44:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   44 |     for(;cnt[v]<adj[v].size();cnt[v]++) {
      |          ~~~~~~^~~~~~~~~~~~~~

• Subtask 1: 38 / 38
• Subtask 2: 17 / 17
• Subtask 3: 45 / 45