Submission #172691

#	Time	Username	Problem	Language	Result	Execution time	Memory
172691		muhammad_hokimiyon	Evacuation plan (IZhO18_plan)	C++14	100 / 100	1055 ms	60176 KiB

plan

#include <bits/stdc++.h>

//#pragma GCC optimize("Ofast")

#define fi first
#define se second
#define ll long long

using namespace std;

const int N = 2e5 + 7;
const int M = 23;
const int mod = 998244353;

int n,m,k,q;
int a[N];
int p[N];
int d[N];
int ans[N];
bool used[N];
set < int > ss[N];
vector < pair < int , int > > v[N];

int get( int x )
{
    return (p[x] == x ? x : p[x] = get(p[x]));
}

void meg( int x , int y , int z )
{
    x = get(x);
    y = get(y);
    if( x == y )return;
    if( (int)ss[x].size() > (int)ss[y].size() )swap(x , y);
    auto it = ss[x].begin();
    while( it != ss[x].end() ){
        int xx = *it;
        if( ss[y].find(xx) != ss[y].end() ){
            ans[xx] = z;
            ss[y].erase(xx);
        }else{
            ss[y].insert(xx);
        }
        it++;
    }
    p[x] = y;
}

void solve1()
{
    cin >> n >> m;
    for( int i = 1; i <= m; i++ ){
        int x,y,z;
        cin >> x >> y >> z;
        v[x].push_back({y , z});
        v[y].push_back({x , z});
    }
    for( int i = 1; i <= n; i++ ){
        p[i] = i;
        d[i] = 1e9;
    }
    set < pair < int , int > > s;
    cin >> k;
    for( int i = 1; i <= k; i++ ){
        int x;
        cin >> x;
        d[x] = 0;
        s.insert({0 , x});
    }
    while( !s.empty() ){
        auto x = *s.begin();
        s.erase(s.begin());
        for( auto y : v[x.se] ){
            if( y.se + d[x.se] < d[y.fi] ){
                s.erase({d[y.fi] , y.fi});
                d[y.fi] = y.se + d[x.se];
                s.insert({d[y.fi] , y.fi});
            }
        }
    }
    vector < pair < int , int > > f;
    for( int i = 1; i <= n; i++ ){
        f.push_back({d[i] , i});
    }
    sort( f.rbegin() , f.rend() );
    cin >> q;
    for( int i = 1; i <= q; i++ ){
        int x,y;
        cin >> x >> y;
        ss[x].insert(i);
        ss[y].insert(i);
    }
    for( int i = 0; i < (int)f.size(); i++ ){
        used[f[i].se] = true;
        for( auto y : v[f[i].se] ){
            if( used[y.fi] ){
                meg(y.fi , f[i].se , f[i].fi);
            }
        }
    }
    for( int i = 1; i <= q; i++ ){
        cout << ans[i] << "\n";
    }
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    //freopen( "input.txt" , "r" , stdin );
    //freopen( "output.txt" , "w" , stdout );

    int cghf = 1;//cin >> cghf;
    while( cghf-- ){
        solve1();
    }
}

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 46 / 46