Submission #57451

#	Time	Username	Problem	Language	Result	Execution time	Memory
57451		top34051	Toy Train (IOI17_train)	C++17	12 / 100	16 ms	1844 KiB

train

#include "train.h"
#include<bits/stdc++.h>
using namespace std;

const int maxn = 5e3 + 5;

int n,m;
int own[maxn], good[maxn];
vector<int> way[maxn], yaw[maxn];

int vis[maxn], deg[maxn], cyc[maxn];
queue<int> q;

int res[maxn];

void getcyc() {
//    printf("solve\n");
    for(int i=0;i<n;i++) vis[i] = deg[i] = 0;
    for(int i=0;i<n;i++) if(good[i]) q.push(i);
    while(!q.empty()) {
        int v = q.front(); q.pop();
        if(good[v] && vis[v]) continue;
        for(auto u : yaw[v]) {
            if(own[u]) {
                if(!vis[u]) {
                    vis[u] = 1;
                    q.push(u);
                }
            }
            else {
                deg[u]++;
                if(!vis[u] && deg[u]==way[u].size()) {
                    vis[u] = 1;
                    q.push(u);
                }
            }
        }
    }
    for(int i=0;i<n;i++) {
        if(good[i] && vis[i]) {
            cyc[i] = 1;
//            printf("cyc %d\n",i);
        }
    }
}

void solve() {
    for(int i=0;i<n;i++) vis[i] = deg[i] = 0;
    for(int i=0;i<n;i++) {
        if(cyc[i]) {
            vis[i] = 1;
            q.push(i);
        }
    }
    while(!q.empty()) {
        int v = q.front(); q.pop();
        for(auto u : yaw[v]) {
            if(own[u]) {
                if(!vis[u]) {
                    vis[u] = 1;
                    q.push(u);
                }
            }
            else {
                deg[u]++;
                if(!vis[u] && deg[u]==way[u].size()) {
                    vis[u] = 1;
                    q.push(u);
                }
            }
        }
    }
    for(int i=0;i<n;i++) res[i] = vis[i];
}

vector<int> who_wins(vector<int> a, vector<int> r, vector<int> u, vector<int> v) {
    n = (int)a.size();
    for(int i=0;i<n;i++) {
        own[i] = a[i];
        good[i] = r[i];
    }
    m = (int)u.size();
    for(int i=0;i<m;i++) {
        way[u[i]].push_back(v[i]);
        yaw[v[i]].push_back(u[i]);
    }
    getcyc();
    solve();
    vector<int> ret;
    for(int i=0;i<n;i++) ret.push_back(res[i]);
    return ret;
}

Compilation message (stderr)

train.cpp: In function 'void getcyc()':
train.cpp:32:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 if(!vis[u] && deg[u]==way[u].size()) {
                               ~~~~~~^~~~~~~~~~~~~~~
train.cpp: In function 'void solve()':
train.cpp:66:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
                 if(!vis[u] && deg[u]==way[u].size()) {
                               ~~~~~~^~~~~~~~~~~~~~~

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