Submission #495173

#	Time	Username	Problem	Language	Result	Execution time	Memory
495173		vinnipuh01	Evacuation plan (IZhO18_plan)	C++17	35 / 100	4075 ms	84472 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>

using namespace std;

const long long oo = 1000000000000000000;

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


/*
    ViHHiPuh

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


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


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

int d[ 100001 ], dd[ 100001 ], p[ 100001 ], dp[ 100001 ][ 20 ];
queue <int> q;
set <pair<int, int> > st;
vector <pair<int, int> > v[ 100001 ];
map <pair<int, int>, bool> mp;

void dfs( int u, int col ) {
	dd[ u ] = col;
	random_shuffle( v[ u ].begin(), v[ u ].end() );
	for ( auto to : v[ u ] ) {
		if ( dd[ to.first ] < min( col, d[ to.first ] ) ) {
			dfs( to.first, min( col, d[ to.first ] ) );
			p[ to.first ] = u;
		}
	}
}

int 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;
		x --;
		y --;
		mp[ { x, y } ] = mp[ { y, x } ] = 1;
		v[ x ].push_back( { y, z } );
		v[ y ].push_back( { x, z } );
	}
	for ( int i = 0; i < n; i ++ )
		d[ i ] = mn;
	int k;
	cin >> k;
	int a;
	for ( int i = 1; i <= k; i ++ ) {
		cin >> a;
		a --;
		q.push( a );
		d[ a ] = 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 );
			}
		}
	}
	int qq;
	cin >> qq;
	int l, r;
	for ( int t = 1; t <= qq; t ++ ) {
		cin >> l >> r;
		l --;
		r --;
		if ( mp[ { l, r } ] )
			cout << min( d[ l ], d[ r ] ) << "\n";
		else {
			if ( n <= 15 && qq <= 200 ) {
				for ( int i = 0; i < ( 1 << n ); i ++ ) {
					for ( int j = 0; j < n; j ++ )
						dp[ i ][ j ] = 0;
				}
				for ( int i = 0; i < n; i ++ )
					dp[ ( 1 << i ) ][ i ] = d[ i ];
				mx = 0;
				for ( int mask = 1; mask < ( 1 << n ); mask ++ ) {
					for ( int i = 0; i < n; i ++ ) {
						if ( mask & ( 1 << i ) ) {
							for ( auto to : v[ i ] ) {
								if ( !( mask & ( 1 << to.first ) ) )
									dp[ ( mask | ( 1 << to.first ) ) ][ to.first ] = max( dp[ ( mask | ( 1 << to.first ) ) ][ to.first ], min( dp[ mask ][ i ], d[ to.first ] ) );
							}
						}
						if ( ( mask & ( 1 << l ) ) && ( mask & ( 1 << r ) ) )
							mx = max( mx, dp[ mask ][ i ] + 0ll);
					}
				}
				cout << mx << "\n";
			}
			else {
				dd[ l ] = d[ l ];
				st.insert( { dd[ l ], l } );
				while ( st.size() ) {
					num = ( --st.end() )->second;
					st.erase( --st.end() );
					for ( auto to : v[ num ] ) {
						if ( dd[ to.first ] < min( dd[ num ], d[ to.first ] ) ) {
							st.erase( { dd[ to.first ], to.first } );
							dd[ to.first ] = min( dd[ num ], d[ to.first ] );
							p[ to.first ] = num;
							st.insert( { dd[ to.first ], to.first } );
						}
					}
				} 
				p[ l ] = -1;
				cout << dd[ r ] << "\n";
				for ( int i = r; ~i; i = p[ i ] )
					dd[ i ] = 0;
			}
		}
	} 
}

/*
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

*/

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 0 / 19
• Subtask 5: 0 / 46