Submission #776982

#	Time	Username	Problem	Language	Result	Execution time	Memory
776982		Trisanu_Das	Arranging Shoes (IOI19_shoes)	C++17	Compilation error	0 ms	0 KiB

shoes

#include <bits/stdc++.h>
using namespace std;
#define ll long long

ll n, BIT[100005];
queue<ll> l_unpair[100005], r_unpair[100005];

void upd(int idx, ll val){
  for(int i = idx; i < n + 1; i += (i & (-i))) BIT[i] += val;
}

ll qry(int idx){
  ll ans = 0;
  for(int i = idx; i > 0; i -= (i & (-i))) ans += BIT[i];
  return ans;
}

ll count_swaps(vector<int> s){
  n = s.size();
  ll swaps = 0;
  for(int i = 1; i < n + 1; i++){
    ll shoe_sz = s[i - 1];
    if(curr_shoe < 0){
      shoe_sz *= -1; // extracting shoe size;
      if(!r_unpair[shoe_sz].empty()){ //has a shoe unpaired of this(shoe_sz) size.
        ll shoe_need = r_unpair[shoe_sz].front; r_unpair[shoe_sz].pop();
        swaps += qry(i) - qry(shoe_need - 1);
        upd(shoe_need, 1);
      }else{ // no shoe.
        l_unpair[shoe_sz].push(i); upd(i, 1);
      }
    }else{
      if(!l_unpair[shoe_sz].empty()){ //has a shoe unpaired of this(shoe_sz) size.
        ll shoe_need = l_unpair[shoe_sz].front; l_unpair[shoe_sz].pop();
        swaps += qry(i) - qry(shoe_need);
        upd(shoe_need, 1);
      }else{ // no shoe.
        r_unpair[shoe_sz].push(i); upd(i, 1);
      }
    }
  }
  return swaps
} 

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:23:8: error: 'curr_shoe' was not declared in this scope
   23 |     if(curr_shoe < 0){
      |        ^~~~~~~~~
shoes.cpp:26:42: error: cannot resolve overloaded function 'front' based on conversion to type 'long long int'
   26 |         ll shoe_need = r_unpair[shoe_sz].front; r_unpair[shoe_sz].pop();
      |                                          ^~~~~
shoes.cpp:34:42: error: cannot resolve overloaded function 'front' based on conversion to type 'long long int'
   34 |         ll shoe_need = l_unpair[shoe_sz].front; l_unpair[shoe_sz].pop();
      |                                          ^~~~~
shoes.cpp:42:15: error: expected ';' before '}' token
   42 |   return swaps
      |               ^
      |               ;
   43 | }
      | ~