Submission #596809

#	Time	Username	Problem	Language	Result	Execution time	Memory
596809		wiwiho	Keys (IOI21_keys)	C++17	100 / 100	1203 ms	245480 KiB

keys

#include <bits/stdc++.h>
#include <bits/extc++.h>
 
#define StarBurstStream ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define iter(a) a.begin(), a.end()
#define riter(a) a.rbegin(), a.rend()
#define lsort(a) sort(iter(a))
#define gsort(a) sort(riter(a))
#define pb(a) push_back(a)
#define eb(a) emplace_back(a)
#define pf(a) push_front(a)
#define ef(a) emplace_front(a)
#define pob pop_back()
#define pof pop_front()
#define mp(a, b) make_pair(a, b)
#define F first
#define S second
#define mt make_tuple
#define gt(t, i) get<i>(t)
#define tomax(a, b) ((a) = max((a), (b)))
#define tomin(a, b) ((a) = min((a), (b)))
#define topos(a) ((a) = (((a) % MOD + MOD) % MOD))
#define uni(a) a.resize(unique(iter(a)) - a.begin())
#define printv(a, b) {bool pvaspace=false; \
for(auto pva : a){ \
    if(pvaspace) b << " "; pvaspace=true;\
    b << pva;\
}\
b << "\n";}
 
using namespace std;
using namespace __gnu_pbds;
 
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
 
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tiii = tuple<int, int, int>;
 
const ll MOD = 1000000007;
const ll MAX = 2147483647;
 
template<typename A, typename B>
ostream& operator<<(ostream& o, pair<A, B> p){
    return o << '(' << p.F << ',' << p.S << ')';
}
 
ll ifloor(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a < 0) return (a - b + 1) / b;
    else return a / b;
}
 
ll iceil(ll a, ll b){
    if(b < 0) a *= -1, b *= -1;
    if(a > 0) return (a + b - 1) / b;
    else return a / b;
}
 
int n, m;
vector<int> R, U, V, C;
vector<vector<pii>> g;
vector<int> dsu, lst;
vector<bool> ok;
vector<int> ans;
vector<int> vst;
vector<queue<pii>> todo;
int cnt = 0, rnd = 0;
 
void init(){
    g.resize(n);
    dsu.resize(n);
    vst.resize(n);
    iota(iter(dsu), 0);
    lst.resize(n);
    todo.resize(n);
    ok.resize(n);
    ans.resize(n, MAX);
}
 
int findDSU(int a){
    if(dsu[a] != a) dsu[a] = findDSU(dsu[a]);
    return dsu[a];
}
 
void unionDSU(int a, int b){
    a = findDSU(a);
    b = findDSU(b);
    dsu[b] = a;
}
 
bool bfs(int s){
    set<int> key;
    queue<int> q;
    q.push(s);
    cnt++;
    vst[s] = cnt;
    int out = -1;
    vector<int> all;
    while(!q.empty()){
        int now = q.front();
        q.pop();
        key.insert(R[now]);
        all.eb(now);
        while(!todo[R[now]].empty()){
            pii nxt = todo[R[now]].front();
            todo[R[now]].pop();
            if(nxt.S != cnt) continue;
            if(vst[nxt.F] == cnt) continue;
            if(findDSU(nxt.F) != s){
                out = nxt.F;
                break;
            }
            vst[nxt.F] = cnt;
            q.push(nxt.F);
        }
        if(out != -1) break;
        for(pii i : g[now]){
            if(vst[i.F] == cnt) continue;
            if(key.find(i.S) != key.end()){
                if(findDSU(i.F) != s){
                    out = i.F;
                    break;
                }
                vst[i.F] = cnt;
                q.push(i.F);
            }
            else{
                todo[i.S].push(mp(i.F, cnt));
            }
        }
        if(out != -1) break;
    }
 
    if(out == -1){
        ok[s] = true;
        for(int i : all){
            ans[i] = all.size();
        }
        return false;
    }
        
    unionDSU(out, s);
    lst[out] = rnd;
    return true;
}
 
bool solve(){
    rnd++;
    
    bool tmp = false;
    for(int i = 0; i < n; i++){
        if(findDSU(i) != i) continue;
        if(lst[i] == rnd) continue;
        if(ok[i]) continue;
        if(bfs(i)) tmp = true;
    }
    return tmp;
}
 
vector<int> find_reachable(vector<int> _r, vector<int> _U, vector<int> _V, vector<int> _C){
    R = _r; U = _U; V = _V; C = _C;
 
    n = R.size();
    m = U.size();
    init();
 
    for(int i = 0; i < m; i++){
        int u = U[i], v = V[i], c = C[i];
        g[u].eb(mp(v, c));
        g[v].eb(mp(u, c));
    }
 
    while(solve());
    
    int mn = *min_element(iter(ans));
    vector<int> owo(n);
    for(int i = 0; i < n; i++){
        if(ans[i] == mn) owo[i] = 1;
    }
 
	return owo;
}

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