Submission #591735

#	Time	Username	Problem	Language	Result	Execution time	Memory
591735		NintsiChkhaidze	Graph (BOI20_graph)	C++14	100 / 100	145 ms	20932 KiB

Graph

#include <bits/stdc++.h>
#define pb push_back
#define s second
#define f first
using namespace std;

const int N = 100005;
vector <pair<int,int> > v[N];
pair <int,double> d[N];
vector <int> pr;
int vis[N],q;
double val;
int p[N];

void dfs(int x){
    pr.pb(x);
    vis[x] = 1;
    for (int i = 0; i < v[x].size(); i++){
        int to = v[x][i].f,col = v[x][i].s,av = -d[x].f;
        double bv = 1.0 - d[x].s;
        if (col == 2) bv+=1.0;

        if (!vis[to]) {
            d[to] = {av,bv};
            p[to] = x;
            dfs(to);
        }else if (av == d[to].f && bv != d[to].s) {
            cout<<"NO";
            exit(0);
        }else if (av == d[to].f && bv == d[to].s){
            continue;
        }else{
            q=1;
            val = (d[to].s - bv)/(av - d[to].f);
        }
    }
}
signed main() {
    ios_base::sync_with_stdio(0),cin.tie(NULL),cout.tie(NULL);
    int n,m;
    cin>>n>>m;

    for (int i = 1; i <= m; i++){
        int a,b,c;
        cin>>a>>b>>c;
        v[a].pb({b,c});
        v[b].pb({a,c});
    }

    for (int i = 1; i <= n; i++){
        if (vis[i]) continue;
        pr.clear(); q=0;
        d[i] = {1,0.0};
        dfs(i);
        if (!q){
            vector <double> vec; vec.clear();
            for (int x: pr)
                vec.pb(-d[x].f*d[x].s);
            sort(vec.begin(),vec.end());
            val = vec[(vec.size())/2];
        }
        for (int x: pr)
            d[x] = {0,val*d[x].f + d[x].s};

        bool check = 1;
        for (int x: pr)
            for (int j = 0; j < v[x].size(); j++){
                int to = v[x][j].f,col = v[x][j].s;
                if (d[x].s + d[to].s != col) check=0;
            }

        if (!check) {
            cout<<"NO";
            exit(0);
        }
    }
    cout<<"YES"<<endl;
    for (int i =1; i <= n;i++)
        cout<<d[i].s<<" ";
}

Compilation message (stderr)

Graph.cpp: In function 'void dfs(int)':
Graph.cpp:18:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   18 |     for (int i = 0; i < v[x].size(); i++){
      |                     ~~^~~~~~~~~~~~~
Graph.cpp: In function 'int main()':
Graph.cpp:67:31: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   67 |             for (int j = 0; j < v[x].size(); j++){
      |                             ~~^~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 12 / 12
• Subtask 3: 17 / 17
• Subtask 4: 24 / 24
• Subtask 5: 42 / 42