Submission #718439

#	Time	Username	Problem	Language	Result	Execution time	Memory
718439		vinnipuh01	Robot (JOI21_ho_t4)	C++17	34 / 100	45 ms	24532 KiB

Main

#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
#define sqrt sqrtl

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;

    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

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

struct Node {
	int dp, u, pr, col;
};

struct cmp {
	bool operator () ( const Node& a, const Node& b ) const {
		if ( a.dp == b.dp ) {
			if ( a.u == b.u ) {
				if ( a.pr == b.pr ) {
					return a.col < b.col;
				}
				return a.pr < b.pr;
			}
			return a.u < b.u;
		}
		return a.dp < b.dp;
	}
};

int n, m, x, y, z[ 2001 ], t[ 2001 ];
int mp[ 2001 ][ 2001 ];
vector <pair<int, int> > v[ 2001 ];
int dp[ 2001 ][ 2001 ][ 2 ];
set <Node, cmp > st;

void dfs( int u, int pr, int col ) {
	int num = 0;
	int pos = 0;
	if ( col == 1 ) {
		for ( auto to : v[ u ] ) {
			if ( to.first == pr )
				num = t[ to.second ], pos = z[ to.second ];
		}
	}
	int sum;
	for ( auto to : v[ u ] ) {
		if ( to.first == pr )
			continue;
		if ( z[ to.second ] == pos )
			sum = num;
		else
			sum = 0;
		if ( dp[ to.first ][ u ][ 1 ] > dp[ u ][ pr ][ col ] + t[ to.second ] ) {
			dp[ to.first ][ u ][ 1 ] = dp[ u ][ pr ][ col ] + t[ to.second ];
			dfs( to.first, u, 1 );
		}
		if ( dp[ to.first ][ u ][ 0 ] > dp[ u ][ pr ][ col ] + mp[ u ][ z[ to.second ] ] - t[ to.second ] - sum ) {
			dp[ to.first ][ u ][ 0 ] = dp[ u ][ pr ][ col ] + mp[ u ][ z[ to.second ] ] - t[ to.second ] - sum;
			dfs( to.first, u, 0 );
		}
	}
}

main () {
	cin >> n >> m;
	for ( int i = 1; i <= m; i ++ ) {
		cin >> x >> y >> z[ i ] >> t[ i ];
		mp[ x ][ z[ i ] ] += t[ i ];
		mp[ y ][ z[ i ] ] += t[ i ];
		v[ x ].push_back( { y, i } );
		v[  y].push_back( { x, i } );
	}
	for ( int i = 2; i <= n; i ++ ) {
		for ( int j = 1; j <= n; j ++ )
			dp[ i ][ j ][ 1 ] = dp[ i ][ j ][ 0 ] = oo;
	}
	st.insert( { 0, 1, 0, 0 } );
	while ( st.size() ) {
		Node u = *st.begin();
		st.erase( st.begin() );
		num = pos = 0;
		if ( u.col == 1 ) {
			for ( auto to : v[ u.u ] ) {
				if ( to.first == u.pr ) {
					num = t[ to.second ], pos = z[ to.second ];
				}
			}
		}
		for ( auto to : v[ u.u ] ) {
			if ( to.first == u.pr )
				continue;
			sum = 0;
			if ( z[ to.second ] == pos )
				sum = num;
			if ( dp[ to.first ][ u.u ][ 1 ] > u.dp + t[ to.second ] ) {
				st.erase( { dp[ to.first ][ u.u ][ 1 ], to.first, u.u, 1 } );
				dp[ to.first ][ u.u ][ 1 ] = u.dp + t[ to.second ];
				st.insert( { dp[ to.first ][ u.u ][ 1 ], to.first, u.u, 1 } );
			}
			if ( dp[ to.first ][ u.u ][ 0 ] > u.dp + mp[ u.u ][ z[ to.second ] ] - t[ to.second ] - sum ) {
				st.erase( { dp[ to.first ][ u.u ][ 0 ], to.first, u.u, 0 } );
				dp[ to.first ][ u.u ][ 0 ] = u.dp + mp[ u.u ][ z[ to.second ] ] - t[ to.second ] - sum;
				st.insert( { dp[ to.first ][u.u  ][ 0 ], to.first, u.u, 0 } );
			}
		}
	}
	mn = oo;
	for ( int i = 1; i <= n; i ++ )
		mn = min( mn, min( dp[ n ][ i ][ 1 ], dp[ n ][ i ][ 0 ] ) );
	if ( mn == oo )
		cout << "-1\n";
	else
		cout << mn << "\n";
}

Compilation message (stderr)

Main.cpp:100:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  100 | main () {
      | ^~~~

• Subtask 1: 34 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42