Submission #864058

#	Time	Username	Problem	Language	Result	Execution time	Memory
864058		manizare	Arranging Tickets (JOI17_arranging_tickets)	C++14	100 / 100	87 ms	28952 KiB

arranging_tickets

#include <bits/stdc++.h> 
 
#pragma GCC optimize("O3,unroll-loops")
#define pb push_back
#define F first
#define S second 
#define all(a) a.begin(),a.end()
#define pii pair <int,int>
#define Pii pair< pii , pii >
#define int long long
using namespace std ;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int maxn = 6e5 + 10 , sq = 3 , maxq = 1e7 + 1 ,  inf = 1e18 + 10 , mod= 998244353 ,lg = 20 ;
vector <pair <pii , int> >  ed ;
vector <int> vec[maxn] ;
int pr[maxn] , n , m ; 
int ch(int val){
  for(int i = 0 ; i < n ; i++){
    pr[i] = 0 ;
  }
  for(int i =0 ; i < ed.size() ; i++){
    pr[ed[i].F.F]+= ed[i].S ; 
    pr[ed[i].F.S]-= ed[i].S ; 
  }
  priority_queue <pair <int  ,pii>  > pq ;
  int w = 0 , ans = 0 ; 
  for(int i = 0 ; i < n ; i++){
    if(i)pr[i] += pr[i-1] ; 
    for(int j = 0  ; j < vec[i].size() ; j++){
      pq.push({ed[vec[i][j]].F.S , {vec[i][j] , ed[vec[i][j]].S}});
    }
    while(pr[i] > val){
      int v = pq.top().S.F , ted = pq.top().S.S; ; 
      pq.pop() ;
      if(ed[v].F.S < i)continue ;
      if(pr[i]-2*ted > val){
        pr[i]-=2*ted;
        pr[ed[v].F.S]+= 2*ted ;
        ans += ted;  
      }else{
        int gp = (pr[i] - val + 1)/2  ;
        pr[i] -= 2*gp ;
        pr[ed[v].F.S]+= 2*gp ;
        ans += gp ; 
        pq.push({ed[v].F.S , {v , ted-gp}})  ;      
      }
    }
  }
  return ans ; 
}
 
signed main() {
  ios::sync_with_stdio(0) ; cin.tie(0) ; cout.tie(0) ;
  cin >> n >> m ;
  for(int i =1 ; i <= m ; i++){
    int a , b , c; 
    cin >> a >> b >> c ;
    if(a > b)swap(a , b) ;
    a--;
    b--;
    pr[a]+=c;
    pr[b]-=c;
    ed.pb({{a, b} , c}) ;
  }
  for(int i = 1; i< n  ;i++){
    pr[i]+= pr[i-1] ; 
  }
  int mx= 0 ; 
  for(int i = 0 ; i < n ; i++){
    if(pr[i] > pr[mx])mx = i ;
  }
  for(int i =0 ; i < ed.size() ; i++){
    ed[i].F.F = (ed[i].F.F - mx - 1+ n)%n ;
    ed[i].F.S = (ed[i].F.S - mx - 1 + n)%n ;
    if(ed[i].F.F  > ed[i].F.S)swap(ed[i].F.F  , ed[i].F.S); 
    vec[ed[i].F.F].pb(i) ;
  }
  cout << min(ch(0) , ch(1)+1) << "\n" ;
}
/*
 
*/

• Subtask 1: 10 / 10
• Subtask 2: 35 / 35
• Subtask 3: 20 / 20
• Subtask 4: 20 / 20
• Subtask 5: 15 / 15