Submission #495352

#	Time	Username	Problem	Language	Result	Execution time	Memory
495352		vinnipuh01	Evacuation plan (IZhO18_plan)	C++17	100 / 100	775 ms	99860 KiB

plan

#include <iostream>
#include <bits/stdc++.h>
#include <cmath>
#include <algorithm>
#include <vector>
#include <deque>
#include <set>
#include <stack>
#include <string>
#include <map>
#include <queue>
#define int long long

using namespace std;

const long long oo = 1000000000000000000;

long long  sum, ans = 0, mx = 0, mn = 1000000000, num, pos;


/*
    ViHHiPuh

   (( `'-""``""-'` ))
     )-__-_.._-__-(
   / --- (o _ o) --- \
   \ .-* ( .0. ) *-. /
   _'-. ,_ '=' _, .-'_
  / `;#'#'# - #'#'#;` \
 \_)) -----'#'----- ((_/
      # --------- #
  '# ------- ------ #'
  /..-'# ------- #'-.\
  _\...-\'# -- #'/-.../_
  ((____)- '#' -(____))


    cout << fixed << setprecision(6) << x;


    freopen ( "sum.in", "r", stdin )
*/

queue <int> q;
int d[ 100001 ], p[ 100001 ], r[ 100001 ], tin[ 100001 ], tout[ 100001 ], tmr;
vector <pair<int, int> > v[ 100001 ];
vector <pair<int, int> > v1[ 100001 ];
vector <pair<int, pair<int, int> > > vv;
int lg = 20;
int par[ 100001 ][ 21 ], mnn[ 100001 ][ 21 ];

int fin( int a ) {
	if ( p[ a ] == a )
		return a;
	return p[ a ] = fin( p[ a ] );
}

void unin( int a, int b ) {
	a = fin( a );
	b = fin( b );
	if ( a == b )
		return;
	if ( r[ a ] < r[ b ] )
		swap( a, b );
	r[ a ] += r[ b ];
	p[ b ] = a;
}

void dfs( int u, int pr = 1 ) {
	par[ u ][ 0 ] = pr;
	tin[ u ] = ++tmr;
	for ( int i = 1; i <= lg; i ++ ) {
		par[ u ][ i ] = par[ par[ u ][ i - 1 ] ][ i - 1 ];
		mnn[ u ][ i ] = min( mnn[ u ][ i - 1 ], mnn[ par[ u ][ i - 1 ] ][ i - 1 ] );
	}
	for ( auto to : v1[ u ] ) {
		if ( to.first != pr )	{
			mnn[ to.first ][ 0 ] = to.second;
			dfs( to.first, u );
		}
	}
	tout[ u ] = tmr;
}

bool ok( int a, int b ) {
	return ( tin[ a ] <= tin[ b ] && tout[ a ] >= tout[ b ] );
}

int lca( int a, int b ) {
	if ( ok( a, b ) )
		return a;
	if ( ok( b, a ) )
		return b;
	for ( int i = lg; i >= 0; i -- ) {
		if ( !ok( par[ a ][ i ], b ) )
			a = par[ a ][ i ];
	}
	return par[ a ][ 0 ];
}

int miin( int a, int b ) {
	sum = d[ b ];
	if ( a == b )
		return sum;
	for ( int i = lg; i >= 0; i -- ) {
		if ( !ok( par[ a ][ i ], b ) ) {
			sum = min( sum, mnn[ a ][ i ] + 0ll);
			a = par[ a ][ i ];
		}
	}
	sum = min( sum, mnn[ a ][ 0 ] + 0ll);
	return sum;
}

main () {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
	int n, m;
	cin >> n >> m;
	int x, y, z;
	for ( int i = 1; i <= m; i ++ ) {
		cin >> x >> y >> z;
		v[ x ].push_back( { y, z } );
		v[ y ].push_back( { x, z } );
	}
	for ( int i = 1; i <= n; i ++ ) {
		r[ i ] = 1;
		p[ i ] = i;
		d[ i ] = oo;
	}
	int k;
	cin >> k;
	for ( int i = 1; i <= k; i ++ ) {
		cin >> num;
		q.push( num );
		d[ num ] = 0;
	}
	while ( q.size() ) {
		num = q.front();
		q.pop();
		for ( auto to : v[ num ] ) {
			if ( d[ to.first ] > d[ num ] + to.second ) {
				d[ to.first ] = d[ num ] + to.second;
				q.push( to.first );
			}
		}
	}
	for ( int i = 1; i <= n; i ++ ) {
		for ( int to = 0; to < v[ i ].size(); to ++ ) {
			v[ i ][ to ].second = min( d[ i ], d[ v[ i ][ to ].first ] );
			vv.push_back( { v[ i ][ to ].second, make_pair( i, v[ i ][ to ].first ) } );
		}
	}
	sort( vv.rbegin(), vv.rend() );
	for ( auto i : vv ) {
		if ( fin( i.second.first ) != fin( i.second.second ) ) {
			unin( i.second.second, i.second.first );
			v1[ i.second.second ].push_back( { i.second.first, min( d[ i.second.first ], d[ i.second.second ] ) } );
			v1[ i.second.first ].push_back( { i.second.second, min( d[ i.second.first ], d[ i.second.second ] ) } );
		}
	}
	dfs( 1 );
	int qq;
	cin >> qq;
	int a[ qq + 1 ], b[ qq + 1 ];
	for ( int i = 1; i <= qq; i ++ ) {
		cin >> a[ i ] >> b[ i ];
		num = lca( a[ i ], b[ i ] );
		cout << min( miin( a[ i ], num ), miin( b[ i ], num ) ) << "\n";
	}
}

/*

9 12
1 9 4
1 2 5
2 3 7
2 4 3
4 3 6
3 6 4
8 7 10
6 7 5
5 8 1
9 5 7
5 4 12
6 8 2
2
4 7
5
1 6
5 3
4 8
5 8
1 5

*/

Compilation message (stderr)

plan.cpp:115:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  115 | main () {
      | ^~~~
plan.cpp: In function 'int main()':
plan.cpp:149:24: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  149 |   for ( int to = 0; to < v[ i ].size(); to ++ ) {
      |                     ~~~^~~~~~~~~~~~~~~

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