Submission #1201558

#	Time	Username	Problem	Language	Result	Execution time	Memory
1201558		Mighilon	Logičari (COCI21_logicari)	C++20	110 / 110	123 ms	32140 KiB

Main

#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 int MOD = 1e9 + 7;

int n;
vector<vi> adj;
vi pa;
struct DSU{
    vi p;
    vi sz;
    DSU(int n){
        p.resize(n);
        F0R(i,n)p[i]=i;
        sz.resize(n);
        F0R(i,n)sz[i]=1;
    }
    int find(int a){
        return p[a]==a?a:p[a]=find(p[a]);
    }
    bool merge(int a, int b){
        int pa=find(a);
        int pb=find(b);
        if(pa==pb)
            return false;
        if(sz[pa]<sz[pb])
            swap(pa,pb);
        sz[pa]+=sz[pb];
        p[pb]=pa;
        return true;
    }
};

void dfs(int v,int p){
    pa[v]=p;
    trav(u,adj[v]){
        if(u==p)continue;
        dfs(u,v);
    }
}

#define int ll
int dp[(int)1e5][2][2][2][2];
int rt,sp;
int f(int v,int cv,int cf,int cr,int cs){
    if(~dp[v][cv][cf][cr][cs]) return dp[v][cv][cf][cr][cs];
    bool good=true;
    if(v==rt&&cr!=cv) good=false;
    if(v==sp&&cv!=cs) good=false;
    if(v==sp&&cr&&cf) good=false;
    if(!good) return dp[v][cv][cf][cr][cs]=1e9;
    bool ccv=true; // next node to color
    if(cf)ccv=false;
    if(v==sp&&cr)ccv=false;
    if(v==rt&&cs)ccv=false;
    int cnt=cv;
    trav(u,adj[v]){
        if(u==pa[v]) continue;
        cnt+=f(u,0,cv,cr,cs);
    }
    int res=1e9;
    if(ccv){
        trav(u,adj[v]){
            if(u==pa[v])continue;
            res=min(res,cnt-f(u,0,cv,cr,cs)+f(u,1,cv,cr,cs));
        }
    }
    else{
        res=min(res,cnt);
    }
    return dp[v][cv][cf][cr][cs]=res;
}

void solve(){
    cin>>n;
    memset(dp,-1,sizeof dp);
    adj.resize(n);
    pa.resize(n);
    DSU dsu(n);
    F0R(i,n){
        int a,b;
        cin>>a>>b;
        a--,b--;
        if(!dsu.merge(a,b)){
            rt=a;
            sp=b;
        }
        else{
            adj[a].pb(b);
            adj[b].pb(a);
        }
    }
    dfs(rt,rt);
    int ans=1e9;
    F0R(i,2)F0R(j,2){
        dbg(f(rt,i,0,i,j),i,j);
        ans=min(ans,f(rt,i,0,i,j));
    }
    if(ans==(int)1e9)
        cout<<-1<<nl;
    else cout<<ans<<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: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 40 / 40
• Subtask 4: 50 / 50