Submission #924485

#	Time	Username	Problem	Language	Result	Execution time	Memory
924485		Cutebol	Commuter Pass (JOI18_commuter_pass)	C++17	0 / 100	2027 ms	36984 KiB

commuter_pass

#include <bits/stdc++.h>
//#include <ext/pb_ds/assoc_container.hpp>
//#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
//using namespace __gnu_pbds;

bool YES(bool f){ if(f) cout << "Yes\n" ; else cout << "No\n" ; return f ; }
void YES(){YES(1);}
void NO(){YES(0);}
void fopn(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
//#define ordered_set tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update>
#define ios ios_base::sync_with_stdio(0) ; cin.tie(0) ; cout.tie(0);
#define int long long
#define ld long double
#define pii pair <int , int>
#define all(x) x.begin() , x.end()
#define ff first
#define ss second
#define endl '\n'

const int N = 2e5 + 5 ;
const int inf = 1e12 ;
const int mod = 1e9 + 8 ;
const double eps = 1e-8 ;

int binpow( int a , int b ){
  if ( b == 0 ) return 1 ;
  int x = binpow ( a , b/2 ) ;
  if ( !(b%2) ) return (x*x) ;
  return (x*x*a) ;
}
template <class T>
bool chmax( T& x , const T& y ){
  bool f = 0 ;
  if ( x < y ) x = y , f = 1 ;
  return f ;
}
template <class T>
bool chmin( T &x , const T &y ){
  bool f = 0 ;
  if ( x > y ) x = y , f = 1 ;
  return f ;
}

//code

int n , m , a , b , c , d , ans = inf ;
vector <pii> g[N] ;
int dis[N][4] ;

void djikstra( int s , int f ){
	set <pii> q ;
	q.insert({0,s}) ;
	for ( int i = 1 ; i <= n ; i ++ ) dis[i][f] = inf ;
	dis[s][f] = 0 ;
	while ( !q.empty() ){
		int v = q.begin()->ss ;
		q.erase(q.begin()) ;
		for ( auto to : g[v] ){
			if ( dis[to.ff][f] > dis[v][f]+to.ss ){
				q.erase({dis[to.ff][f],to.ff}) ;
				dis[to.ff][f] = dis[v][f] + to.ss ;
				q.insert({dis[to.ff][f],to.ff}) ;
			}
		} 
	}
}

void bfs ( int s ){
	for ( int i = 1 ; i <= n ; i ++ ) dis[i][3] = inf ;
	dis[s][3] = 0 ; 
	set <pair < int , pair <int , pii>>> q ;
	q.insert({0,{s,{dis[s][1],dis[s][2]}}}) ;
	while ( !q.empty() ){
		int v = q.begin()->ss.ff ;
		int ma = q.begin()->ss.ss.ff ;
		int mb = q.begin()->ss.ss.ss ;
		q.erase(q.begin()) ;
		for ( auto to : g[v] ){
			if ( dis[to.ff][3] > dis[v][3] + to.ss || ( dis[to.ff][3] == dis[v][3] + to.ss && ( dis[to.ff][1] < ma || dis[to.ff][2] < mb ) ) ){
				if ( to.ff == b && dis[v][3] + to.ss == dis[b][0] ){
					chmin ( ans , min(ma,dis[to.ff][1])+min(mb,dis[to.ff][2]) ) ;
					continue ;
				}
				q.erase({dis[to.ff][3],{to.ff,{min(ma,dis[to.ff][1]),min(mb,dis[to.ff][2])}}}) ;
				dis[to.ff][3] = dis[v][3] + to.ss ;
				q.insert({dis[to.ff][3],{to.ff,{min(ma,dis[to.ff][1]),min(mb,dis[to.ff][2])}}}) ;
			}
		}
	}
}

void solve(){
	
	cin >> n >> m >> a >> b >> c >> d ;
	for ( int i = 0 ; i < m ; i ++ ){
		int x , y , c ; cin >> x >> y >> c ;
		g[x].push_back({y,c}) ;
		g[y].push_back({x,c}) ;
	}
	djikstra( a , 0 ) ;
	djikstra( c , 1 ) ;
	djikstra( d , 2 ) ;
	bfs(a) ; chmin ( ans , dis[d][1] ) ;
	cout << ans ;
}

signed main(){
    ios ;
	int t = 1 ;
	//cin >> t ;
	while ( t -- ) solve() ;
}

Compilation message (stderr)

commuter_pass.cpp: In function 'void fopn(std::string)':
commuter_pass.cpp:10:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 | void fopn(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
commuter_pass.cpp:10:72: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 | void fopn(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                                 ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 16
• Subtask 2: 0 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 45