Submission #249184

#	Time	Username	Problem	Language	Result	Execution time	Memory
249184		MarcoMeijer	Toy Train (IOI17_train)	C++14	0 / 100	2091 ms	4344 KiB

train

#include "train.h"
#include <bits/stdc++.h>
using namespace std;
 
//macros
typedef long long ll;
typedef pair<int, int> ii;
typedef pair<ll, ll> lll;
typedef tuple<int, int, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<iii> viii;
typedef vector<ll> vll;
typedef vector<lll> vlll;
#define REP(a,b,c) for(int a=int(b); a<int(c); a++)
#define RE(a,c) REP(a,0,c)
#define RE1(a,c) REP(a,1,c+1)
#define REI(a,b,c) REP(a,b,c+1)
#define REV(a,b,c) for(int a=int(c-1); a>=int(b); a--)
#define INF 1e9
#define pb push_back
#define fi first
#define se second
#define sz size()
 
const int MX=6000;
 
int n, m;
vi a, r, u, v;
vi res;
set<int> adj[MX], rev[MX];
int cnt[MX];
set<int> R;

set<int> f(bool A, set<int> x) { // O(n+m)
    set<int> ret;
    queue<int> q;
    RE(u,n) cnt[u] = 0;
    for(int u : x) q.push(u), cnt[u]++;
    while(!q.empty()) {
        int u = q.front(); q.pop();
        ret.insert(u);
        for(int v:rev[u]) {
            cnt[v]++;
            if(a[v] ==  A) {
                if(cnt[v] == 1) q.push(v);
            } else {
                if(cnt[v] == adj[v].sz) q.push(v);
            }
        }
    }
    return ret;
}
set<int> getInv(set<int> x) {
    set<int> y;
    RE(u,n) if(!x.count(u)) y.insert(u);
    return y;
}
void removeFromGraph(int u) {
    for(int v:adj[u]) rev[v].erase(u);
    for(int v:rev[u]) adj[v].erase(u);
    adj[u].clear();
    rev[u].clear();
}
 
vi who_wins(vi A, vi _R, vi U, vi V) {
    a = A; r = _R; u = U; v = V;
    n = a.size(); m = u.size();
    res.resize(n);
 
    RE(i,m) adj[u[i]].insert(v[i]);
    RE(i,m) rev[v[i]].insert(u[i]);

    RE(u,n) if(r[u]) R.insert(u);

    set<int> y = f(1, R);
    if(y.sz == n) {
        RE(u,n) res[u] = 1;
        return res;
    }
    RE(u,n) res[u] = 1;
    while(1) {
        set<int> x = getInv(f(1, R));
        set<int> y = f(0,x);
        for(int u:y) res[u] = 0;
        for(int u:y) removeFromGraph(u);
        if(y.size() == 0) break;
    }
 
	return res;
}

Compilation message (stderr)

train.cpp: In function 'std::set<int> f(bool, std::set<int>)':
train.cpp:48:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 if(cnt[v] == adj[v].sz) q.push(v);
                           ^
train.cpp: In function 'vi who_wins(vi, vi, vi, vi)':
train.cpp:77:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     if(y.sz == n) {
        ~~~~~^~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 11
• Subtask 4: 0 / 11
• Subtask 5: 0 / 12
• Subtask 6: 0 / 51