Submission #748745

#	Time	Username	Problem	Language	Result	Execution time	Memory
748745		grogu	Keys (IOI21_keys)	C++17	100 / 100	1206 ms	143352 KiB

keys

#define here cerr<<"===========================================\n"
#define dbg(x) cerr<<#x<<": "<<x<<endl;
#include <bits/stdc++.h>
#define ld double
#define ll int
#define ull unsigned long long
#define llinf 100000000000000000LL // 10^17
#define iinf 2000000000 // 2*10^9
#define pb push_back
#define popb pop_back
#define fi first
#define sc second
#define endl '\n'
#define pii pair<int,int>
#define pll pair<ll,ll>
#define pld pair<ld,ld>
#define all(a) a.begin(),a.end()
#define ceri(a,l,r) {cerr<<#a<<": ";for(ll i_ = l;i_<=r;i_++) cerr<<a[i_]<< " ";cerr<<endl;}
#define cer(a) {cerr<<#a<<": ";for(ll x_ : a) cerr<<x_<< " ";cerr<<endl;}
#define si(a) (ll)(a.size())
using namespace std;

#define maxn 300005
ll n,m;
vector<pll> g[maxn];
set<ll> key[maxn];
map<ll,vector<ll> > mp[maxn];
vector<ll> use[maxn];
ll a[maxn];
vector<ll> ans;
ll dsu[maxn],sz[maxn];
ll root(ll x){
    while(x!=dsu[x]){
        dsu[x] = dsu[dsu[x]];
        x = dsu[x];
    }
    return x;
}
ll par[maxn];
void upd(ll x,ll y){
    x = root(x); y = root(y);
    ll fa = par[y];
    if(sz[x]<sz[y]) swap(x,y);
    dsu[y] = x;
    sz[x]+=sz[y];
    for(ll z : use[y]) use[x].pb(z);
    for(auto it : mp[y]){
        for(ll z : it.sc){
            if(key[x].count(it.fi)==0){
                mp[x][it.fi].pb(z);
            }else{
                use[x].pb(z);
            }
        }
    }
    for(ll z : key[y]){
        while(mp[x][z].size()){
            use[x].pb(mp[x][z].back());
            mp[x][z].popb();
        }
        key[x].insert(z);
    }
    par[x] = fa;
    vector<ll>().swap(use[y]);
    map<ll,vector<ll> >().swap(mp[y]);
    set<ll>().swap(key[y]);
}
bool check0(){
    bool bad = 0;
    for(ll i = 1;i<=n;i++){
        ll cnt = 0;
        for(pll p : g[i]){
            if(p.sc==a[i]) cnt++;
        }
        if(cnt==0) ans[i] = 1,bad = 1;
    }
    return bad;
}
ll dsu2[maxn];
ll sz2[maxn];
ll root2(ll u){
    while(u!=dsu2[u]){
        dsu2[u] = dsu2[dsu2[u]];
        u = dsu2[u];
    }
    return u;
}
void upd2(ll x,ll y){
    x = root2(x); y = root2(y);
    if(sz2[x]>sz2[y]) swap(x,y);
    dsu2[x] = y;
    sz2[y]+=sz2[x];
}
vector<int> find_reachable(vector<int> r,vector<int> u,vector<int> v,vector<int> c) {
    n = si(r);
    m = si(u);
    for(ll i = 1;i<=n;i++) a[i] = r[i-1];
    for(ll i = 1;i<=m;i++){
        ll x,y,w;
        x = u[i-1];
        y = v[i-1];
        w = c[i-1];
        x++; y++;
        g[x].pb({y,w});
        g[y].pb({x,w});
    }
    ans.resize(n+1);
    iota(dsu+1,dsu+1+n,1);
    iota(dsu2+1,dsu2+1+n,1);
    fill(sz+1,sz+1+n,1);
    fill(sz2+1,sz2+1+n,1);
    for(ll i = 1;i<=n;i++){
        for(pll p : g[i]){
            ll j = p.fi,z = p.sc;
            if(z==a[i]){
                use[i].pb(j);
            }else{
                mp[i][z].pb(j);
            }
        }
        key[i].insert(a[i]);
    }
    vector<ll> roots;
    for(ll i = 1;i<=n;i++) roots.pb(i);
    ll mn = llinf;
    set<ll> res;
    while(roots.size()){
        ll i = roots.back();
        i = root(i);
        roots.popb();
        while(use[i].size()){
            ll j = use[i].back();
            use[i].popb();
            j = root(j);
            if(root(i)==root(j)) continue;
            if(root2(i)==root2(j)){
                while(par[j]){
                    upd(j,par[j]);
                    j = root(j);
                }
                i = root(i);
            }else{
                par[i] = j;
                upd2(i,j);
                break;
            }
        }
        if(!par[i]){
            if(sz[i]<mn){
                mn = sz[i];
                res.clear();
                res.insert(i);
            }else if(sz[i]==mn) res.insert(i);
        }
    }
    for(ll i = 1;i<=n;i++) if(res.count(root(i))) ans[i] = 1;
    reverse(all(ans));
    ans.popb();
    reverse(all(ans));
	return ans;
}
/**
4 5
0 1 1 2
0 1 0
0 2 0
1 2 1
1 3 0
3 1 2

3 1
0 0 0
0 1 0

7 10
0 1 1 2 2 1 2
0 1 0
0 2 0
1 2 1
1 3 0
2 3 0
3 4 1
3 5 2
4 5 0
4 6 2
5 6 1
**/

Compilation message (stderr)

keys.cpp: In function 'std::vector<int> find_reachable(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
keys.cpp:7:15: warning: overflow in conversion from 'long long int' to 'int' changes value from '100000000000000000' to '1569325056' [-Woverflow]
    7 | #define llinf 100000000000000000LL // 10^17
      |               ^~~~~~~~~~~~~~~~~~~~
keys.cpp:125:13: note: in expansion of macro 'llinf'
  125 |     ll mn = llinf;
      |             ^~~~~

• Subtask 1: 9 / 9
• Subtask 2: 11 / 11
• Subtask 3: 17 / 17
• Subtask 4: 30 / 30
• Subtask 5: 33 / 33