Submission #339296

#	Time	Username	Problem	Language	Result	Execution time	Memory
339296		Dilshod_Imomov	Evacuation plan (IZhO18_plan)	C++17	100 / 100	1140 ms	189036 KiB

plan

# include <bits/stdc++.h>
# define speed ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
# define int long long
# define fi first
# define se second
 
using namespace std;
 
const int N = 2e6 + 7;
const int mod = 1e9 + 7;

vector < pair < int, int > > adj[N];
int dist[N], n, m, go, pr[N], ans[N], sz[N];
bool used[N];
set < int > st[N];

int find_set( int a ) {
    if ( a == pr[a] ) {
        return a;
    }
    return find_set(pr[a]);
}

void merge( int a, int b, int val ) {
    int x = find_set(a);
    int y = find_set(b);
    if ( x == y ) {
        return;
    }
    if ( sz[x] < sz[y] ) {
        swap( x, y );
    }
    for ( auto i: st[y] ) {
        if ( st[x].count(i) ) {
            ans[ i ] = val;
        }
        else {
            st[x].insert(i);
        }
    }
    st[y].clear();
    pr[y] = x;
    sz[x] += sz[y];
}

int32_t main() {
    speed;
    cin >> n >> m;
    for ( int i = 1; i <= m; i++ ) {
        int u, v, w;
        cin >> u >> v >> w;
        adj[u].push_back( { v, w } );
        adj[v].push_back( { u, w } );
    }
    for ( int i = 1; i <= n; i++ ) {
        dist[i] = 1e12;
        pr[i] = i;
        sz[i] = 1;
    }
    int k;
    cin >> k;
    set < pair < int, int > > q;
    for ( int i = 1; i <= k; i++ ) {
        int x;
        cin >> x;
        q.insert( { 0, x } );
        dist[x] = 0;
    }
    while ( !q.empty() ) {
        int v = q.begin()->se;
        q.erase( q.begin() );
        for ( auto pr: adj[v] ) {
            int u = pr.fi, w = pr.se;
            if ( dist[u] > dist[v] + w ) {
                q.erase( { dist[u], u } );
                dist[u] = dist[v] + w;
                q.insert( { dist[u], u } );
            }
        }
    }
    int qr;
    cin >> qr;
    for ( int i = 1; i <= qr; i++ ) {
        int x, y;
        cin >> x >> y;
        st[x].insert(i);
        st[y].insert(i);
    }
    vector < pair < int, int > > vc;
    for ( int i = 1; i <= n; i++ ) {
        vc.push_back( { dist[i], i } );
    }
    sort( vc.rbegin(), vc.rend() );
    for ( int i = 0; i < n; i++ ) {
        int x = vc[i].se;
        used[x] = 1;
        // cout << x << endl;
        for ( auto pr: adj[x] ) {
            int u = pr.fi;
            if ( used[u] ) {
                merge( x, u, dist[x] );
            }
        }
    }
    for ( int i = 1; i <= qr; i++ ) {
        cout << ans[i] << '\n';
    }
}

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