Submission #1183454

#	Time	Username	Problem	Language	Result	Execution time	Memory
1183454		Mighilon	Newspapers (CEOI21_newspapers)	C++20	0 / 100	1 ms	324 KiB

newspapers

#include <bits/stdc++.h>
using namespace std;
 
#ifdef DEBUG
#include "../Library/debug.h"
#else
#define dbg(x...)
#endif

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<ll> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl; 
 
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) for (int i = 0; i < (a); ++i)
#define FORd(i, a, b) for (int i = (b) - 1; i >= (a); --i)
#define F0Rd(i, a) for (int i = (a) - 1; i >= 0; --i)
#define trav(a, x) for (auto& a : x)
#define f first 
#define s second
#define pb push_back
#define sz(x) (int)(x).size()
#define all(x) x.begin(), x.end()
 
const char nl = '\n';
const int INF = 1e9;
const ll MOD = 998244353;
const int mxN = 3e5+5;

struct DSU{
    int n;
    vi p;
    vi sz;
    DSU(int _n){
        n=_n;
        p.resize(n);
        iota(all(p),0);
        sz.resize(n);
        fill(all(sz),1);
    }
    int find(int a){
        return p[a]==a?a:p[a]=find(p[a]);
    }
    bool merge(int a, int b){
        if(find(a)==find(b))return false;
        int pa=find(a);
        int pb=find(b);
        if(sz[pa]<sz[pb])swap(pa,pb);
        sz[pa]+=sz[pb];
        p[pb]=pa;
        return true;
    }
};

void solve(){
    int n,m;
    cin>>n>>m;
    vector<vi> adj(n);
    DSU dsu(n);
    bool ans=true;
    F0R(i,m){
        int a,b;
        cin>>a>>b;
        --a,--b;
        adj[a].pb(b);
        adj[b].pb(a);
        if(!dsu.merge(a,b)){
            ans=false;
        }
    }
    if(ans){
        cout<<"YES"<<nl;
    }
    else{
        cout<<"NO"<<nl;
    }
}
int32_t main(){
    ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);

    int TC = 1;
    // cin >> TC;
    while(TC--){
        solve();
    }
    return 0;
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 8
• Subtask 3: 0 / 80