Submission #139781

#	Time	Username	Problem	Language	Result	Execution time	Memory
139781		CaroLinda	통행료 (IOI18_highway)	C++14	51 / 100	376 ms	262148 KiB

highway

#include "highway.h"
#include <bits/stdc++.h>

#define debug 
#define lp(i,a,b) for(int i=a;i<b;i++)
#define pii pair<int,int>
#define ll long long
#define ff first
#define ss second
#define pb push_back
#define mk make_pair

const int MAXN = 9e4+ 10 ;
const int MAXM = 13e4+10 ;

using namespace std ;

struct Edge
{

	int j , id ;

	Edge(int j = 0 , int id = 0) 
		: j(j) , id(id) {}

} ;

int n , m , S , T ;

int edgePai[MAXN] , ini[MAXN] , fim[MAXN] ;

pii edge[MAXM] ;

vector<int> toAsk , possible ;

ll rad , Prev ;

vector<Edge> adj[MAXN] ;

bool marc[MAXN] ;

// --------------------------------


void prepareDfs()
{
	memset(marc,false, sizeof marc) ;
	possible.resize(0) ;
}

void dfs(int x , ll depth , ll curRad , bool allowed[])
{

	if( depth == curRad ) possible.pb(x) ;
	marc[x] = true ;

	for( Edge e : adj[x] )
		if( !marc[e.j] && allowed[e.id] )
		{
			edgePai[e.j] = e.id ;
			dfs( e.j , depth+1, curRad , allowed ) ;
		}

}


int findSpecial(int s , bool allowed[] , ll curRad ) 
{

	if( curRad == 0 ) return s ;

	debug("%d %lld\n" , s  ,curRad) ;
	lp(i,0,m) debug("%d " , allowed[i] == true ? 1 : 0) ;
	debug("\n") ;

	prepareDfs() ;	
	dfs(s , 0 , curRad , allowed) ;

	int l = 0 , r = possible.size() - 1 , mid , best=0 ;

	while( l <= r )
	{
		mid = (l+r)/2 ;

		lp(i,l,mid+1) toAsk[ edgePai[ possible[i] ] ] = 1 ;

		ll newTot = ask(toAsk) ;

		lp(i,l,mid+1) toAsk[ edgePai[ possible[i] ] ] = 0 ;

		if( newTot > Prev ) 
		{
			r = mid - 1 ;
			best = mid ;
		}

		else l = mid+1 ;

	}

	return possible[best] ;


}

// --------------------------------

vector<int> grupo[2] ;

void dfs(int x , int edgeId , int idx )
{

	for( Edge e : adj[x] )
		if( edgeId != e.id )
		{
			grupo[idx].pb(e.id) ;
			dfs(e.j,e.id, idx) ;
		}

}


bool allowed[MAXM] ;

void find_pair(int N, vector<int> U, vector<int> V, int A, int B) {
  
  m = U.size();
  n = N ;

  lp(i,0,m)
  {

  		
  	int a = U[i] , b = V[i] ;

  	adj[a].pb(Edge(b,i)) ;
  	adj[b].pb(Edge(a,i)) ;

  	toAsk.pb(0) ;
  	allowed[i] = 1 ;
  	edge[i] = mk(a,b) ;

  }

  Prev = ask(toAsk) ;
  rad = Prev/A ;
  

  int l = 0 , r = m-1 , mid , best =0 ;

  while(l<=r)
  {

  	mid = (l+r)/2 ;

  	lp(i,l,mid+1) toAsk[i] = 1 ;

  	ll newTot = ask(toAsk) ;

  	lp(i,l,mid+1) toAsk[i] = 0 ;

  	if( newTot > Prev ) 
  	{
  		r = mid - 1 ;
  		best = mid ;
  	}

  	else l = mid+1 ;

  }

  
  pii myEdge = edge[best] ;

  dfs(myEdge.ff , best , 0) ;
  dfs(myEdge.ss, best, 1) ;

  debug("Found %d %d\n" , myEdge.ff, myEdge.ss) ;

  for(int i : grupo[0]) debug("%d " ,  i) ;
  debug("\n") ;

  for(int i : grupo[1]) debug("%d " , i ) ;
  debug("\n") ;

	
	for(int i : grupo[0]) toAsk[i] = 1 ;

	ll newTot = (ask(toAsk) - Prev) / (B-A) ;

	
	memset(allowed, false, sizeof allowed) ;

	for(int i : grupo[0]) 
	{
		toAsk[i] = 0 ;
		allowed[i] = true ;
	}

	S = findSpecial( myEdge.ff , allowed , newTot ) ;

	for(int i : grupo[0]) allowed[i] = false ;
	for(int i : grupo[1]) allowed[i] = true ;

	T = findSpecial(myEdge.ss , allowed, rad  - newTot- 1) ;

	answer(S,T) ;

}
 

Compilation message (stderr)

highway.cpp: In function 'int findSpecial(int, bool*, long long int)':
highway.cpp:72:22: warning: left operand of comma operator has no effect [-Wunused-value]
  debug("%d %lld\n" , s  ,curRad) ;
                      ^
highway.cpp:72:26: warning: right operand of comma operator has no effect [-Wunused-value]
  debug("%d %lld\n" , s  ,curRad) ;
                          ^~~~~~
highway.cpp:73:51: warning: left operand of comma operator has no effect [-Wunused-value]
  lp(i,0,m) debug("%d " , allowed[i] == true ? 1 : 0) ;
                                                   ^
highway.cpp:74:14: warning: statement has no effect [-Wunused-value]
  debug("\n") ;
              ^
highway.cpp: In function 'void find_pair(int, std::vector<int>, std::vector<int>, int, int)':
highway.cpp:8:12: warning: left operand of comma operator has no effect [-Wunused-value]
 #define ff first
            ^
highway.cpp:178:34: note: in expansion of macro 'ff'
   debug("Found %d %d\n" , myEdge.ff, myEdge.ss) ;
                                  ^~
highway.cpp:8:12: warning: right operand of comma operator has no effect [-Wunused-value]
 #define ff first
            ^
highway.cpp:178:34: note: in expansion of macro 'ff'
   debug("Found %d %d\n" , myEdge.ff, myEdge.ss) ;
                                  ^~
highway.cpp:180:40: warning: left operand of comma operator has no effect [-Wunused-value]
   for(int i : grupo[0]) debug("%d " ,  i) ;
                                        ^
highway.cpp:181:15: warning: statement has no effect [-Wunused-value]
   debug("\n") ;
               ^
highway.cpp:183:39: warning: left operand of comma operator has no effect [-Wunused-value]
   for(int i : grupo[1]) debug("%d " , i ) ;
                                       ^
highway.cpp:184:15: warning: statement has no effect [-Wunused-value]
   debug("\n") ;
               ^

• Subtask 1: 5 / 5
• Subtask 2: 7 / 7
• Subtask 3: 6 / 6
• Subtask 4: 33 / 33
• Subtask 5: 0 / 18
• Subtask 6: 0 / 31