Submission #802079

#	Time	Username	Problem	Language	Result	Execution time	Memory
802079		lollipop	Stations (IOI20_stations)	C++17	0 / 100	599 ms	11556 KiB

stations

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
#define ll long long
#define pb push_back
#define s second
#define f first
#define pf push_front
#define inf 100000000000000000
#define bitebi __builtin_popcountll
#define FOR( i , n ) for( int i = 0 ; i < n ; i ++ )
#define YES cout <<"YES\n"
#define NO cout << "NO\n"
#define debug cout << "Here Fine" << endl ;
#define pr pair < int , int >
#define fbo find_by_order // returns iterator
#define ook order_of_key // returns strictly less numbers than key
using namespace std ;
//#pragma GCC optimize("Ofast")
//#pragma GCC target("avx,avx2,fma")
using namespace __gnu_pbds;
using namespace __gnu_cxx;
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
const double Pi=acos(-1.0);
const double EPS=1E-8;
const int mod =  1000000007 ;
const int mod1 = 998244353 ;
const int NN = 2e5 + 10 ;
mt19937 R(time(0));
map < int , int > ma , ma1 ;

//#include "stations.h"

vector < int > v[ NN ] ;
int hh[ NN ] , timer = 0 ;
pair < int , int > tt[ NN ] ;
void dfs( int node , int parent , int h ){
     hh[ node ] = h ;
     tt[ node ].f = timer ; timer ++ ;
     for( auto x : v[ node ] ){
        if( x == parent ) continue ;
        dfs( x , node , h + 1 ) ; 
     }
     tt[ node ].s = timer ; timer ++ ;
}
vector<int> label(int n, int k, vector<int> U, vector<int> V){
  FOR( i , n ) v[ i ].clear() ;
     FOR( i , n - 1 ){
        v[ U[ i ] ].pb( V[ i ] ) ;
        v[ V[ i ] ].pb( U[ i ] ) ;
     }
     dfs( 0 , -1 , 0 ) ;
     set < pair < int , int > > se ;
     FOR( i , n ){
       se.insert( { tt[ i ].f , 0 } ) ;
       se.insert( { tt[ i ].s , 1 } ) ;
     }
     int cnt = 0 ;
     int mx = 0 , cur = 0 ;
     set < int > se1 , se2 ;
     FOR( i , 10 * n ){
      se1.insert( cur ) ; 
      se2.insert( cur + 1 ) ; cur += 2 ; 
     }
     for( auto x : se ){
       int nd ;
       if( x.s == 0 ){
         nd = *se1.upper_bound( mx ) ;
         mx = nd ;
       }
       else{
         nd = *se2.upper_bound( mx ) ;
         mx = nd ;
       }
       ma[ x.f ] = nd ; 
     }
     vector < int > rt ; 
     FOR( i , n ){
      if( hh[ i ] % 2 == 0 ){
         rt.pb( { ma[ tt[ i ].f ] } ) ;
      }
      else{
        rt.pb( { ma[ tt[ i ].s ] } ) ;
      }
     }
     return rt ;
}

int find_next_station(int s, int t, vector<int> c){
    if( c.size() == 1) return c[ 0 ] ;
    int ss = c.size() ;
    if( s % 2 == 0 ){
        // anu gaqvs in-i
      if( t % 2 == 0 ){
         if( t < s ) return c[ ss - 1 ] ;
         if( t > c[ ss - 2 ] ) return c[ ss - 1 ] ;
         for( auto x : c ) if( x > t ) return x ;
      }
      else{
        if( t < s ) return c[ ss - 1 ] ;
        if( t > c[ ss - 2 ] ) return c[ ss - 1 ] ; 
        for( auto x : c ) if( x > t ) return x ;
      }
    }
    else{
      if( t % 2 == 0 ){
         if( t > s ) return c[ ss - 1 ] ;
         if( t < c[ 0 ] ) return c[ ss - 1 ] ;
         FOR( i , ss ){
          if( c[ i ] > t ) return c[ i - 1 ] ;
         }
      }
      else{
         if( t > s ) return c[ ss - 1 ] ;
         if( t < c[ 0 ] ) return c[ ss - 1 ] ;
         FOR( i , ss ){
          if( c[ i ] > t ) return c[ i - 1 ] ;
         }
      }     
    }

}




// static int max_label = 0;
// static int r, n, k, q;
// static std::vector<int> u, v, labels, answers;
// static std::map<int, int> reverse_labels;
// static std::vector<std::vector<int>> adjlist;
// static int s, t, w;
// static std::vector<int> c;

// int main() {
// 	assert(scanf("%d", &r) == 1);
// 	for (int tc = 0; tc < r; tc++) {
// 		assert(scanf("%d%d", &n, &k) == 2);
// 		u.resize(n - 1);
// 		v.resize(n - 1);
// 		adjlist.clear();
// 		adjlist.resize(n);
// 		for (int i = 0; i < n - 1; i++) {
// 			assert(scanf("%d%d", &u[i], &v[i]) == 2);
// 			adjlist[u[i]].push_back(v[i]);
// 			adjlist[v[i]].push_back(u[i]);
// 		}
// 		labels = label(n, k, u, v);
// 		if ((int)labels.size() != n) {
// 			printf("Number of labels not equal to %d\n", n);
// 			exit(0);
// 		}
// 		reverse_labels.clear();
// 		for (int i = 0; i < n; i++) {
// 			if (labels[i] < 0 || labels[i] > k) {
// 				printf("Label not in range 0 to %d\n", k);
// 				exit(0);
// 			}
// 			if (reverse_labels.find(labels[i]) != reverse_labels.end()) {
// 				printf("Labels not unique\n");
// 				exit(0);
// 			}
// 			reverse_labels[labels[i]] = i;
// 			if (labels[i] > max_label) {
// 				max_label = labels[i];
// 			}
// 		}
// 		assert(scanf("%d", &q) == 1);
// 		for (int i = 0; i < q; i++) {
// 			assert(scanf("%d%d%d", &s, &t, &w) == 3);
// 			c.clear();
// 			for (int v : adjlist[s]) {
// 				c.push_back(labels[v]);
// 			}
// 			std::sort(c.begin(), c.end());
// 			int answer = find_next_station(labels[s], labels[t], c);
// 			if (!std::binary_search(c.begin(), c.end(), answer)) {
// 				printf("Label %d returned by find_next_station not found in c\n", answer);
// 				exit(0);
// 			}
// 			answers.push_back(reverse_labels[answer]);
// 		}
// 	}
// 	printf("%d\n", max_label);
// 	for (int index : answers) {
// 		printf("%d\n", index);
// 	}
// 	exit(0);
// }

Compilation message (stderr)

stations.cpp: In function 'std::vector<int> label(int, int, std::vector<int>, std::vector<int>)':
stations.cpp:59:10: warning: unused variable 'cnt' [-Wunused-variable]
   59 |      int cnt = 0 ;
      |          ^~~
stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:123:1: warning: control reaches end of non-void function [-Wreturn-type]
  123 | }
      | ^

• Subtask 1: 0 / 5
• Subtask 2: 0 / 8
• Subtask 3: 0 / 16
• Subtask 4: 0 / 10
• Subtask 5: 0 / 61