Submission #364791

#	Time	Username	Problem	Language	Result	Execution time	Memory
364791		wind_reaper	Carnival Tickets (IOI20_tickets)	C++17	Compilation error	0 ms	0 KiB

tickets

#include "tickets.h"
#include <bits/stdc++.h>
 
using namespace std;
 
long long find_maximum(int k, vector<vector<int>> x) {
	int n = x.size(); 
	int m = x[0].size();
 
	vector<vector<int>> ans(n, vector<int>(m, -1));
 
	long long a = 0; 
 
	for(int i = 0; i < n; i++){
		for(int j = m-1; j >= m-k; --j){
			ans[i][j] = (m-1-j);
			a += 1LL*x[i][j];
		}
	}
 
	vector<array<int, 4>> b;
 
	for(int i = 0; i < n; i++){
		for(int j = 0; j < k; j++)
			for(int w = m-1; w >= m-k; --w)
				if(i == j){
					b.push_back({0, i, j, w});
					continue;
				}
				b.push_back({x[i][j] + x[i][w], i, j, w});
	}
 
	sort(b.begin(), b.end()); 
	for(auto& [red, row, mn, mx] : b){
		if(ans[row][mx] == -1 || ans[row][mn] != -1)
			continue;
		a -= 1LL*red;
		swap(ans[row][mx], ans[row][mn]);
	}
 
	allocate_tickets(ans);
	return a;
}
/*
for every i, j < k exchange the i th minimum and j th maximum 
each exchange costs x[i] + x[j] ... take the first nk/2 valid exchanges
 
the actual order of the stuff doesnt matter
you wanna choose nk/2 pairs to remove
 
what happens when the stuff starts to overlap

...|..|...
..|.|..
*/ 

Compilation message (stderr)

tickets.cpp: In function 'long long int find_maximum(int, std::vector<std::vector<int> >)':
tickets.cpp:25:4: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   25 |    for(int w = m-1; w >= m-k; --w)
      |    ^~~
tickets.cpp:30:5: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for'
   30 |     b.push_back({x[i][j] + x[i][w], i, j, w});
      |     ^
tickets.cpp:30:23: error: 'j' was not declared in this scope
   30 |     b.push_back({x[i][j] + x[i][w], i, j, w});
      |                       ^
tickets.cpp:30:33: error: 'w' was not declared in this scope
   30 |     b.push_back({x[i][j] + x[i][w], i, j, w});
      |                                 ^
tickets.cpp:30:45: error: no matching function for call to 'std::vector<std::array<int, 4> >::push_back(<brace-enclosed initializer list>)'
   30 |     b.push_back({x[i][j] + x[i][w], i, j, w});
      |                                             ^
In file included from /usr/include/c++/9/vector:67,
                 from tickets.h:1,
                 from tickets.cpp:1:
/usr/include/c++/9/bits/stl_vector.h:1184:7: note: candidate: 'void std::vector<_Tp, _Alloc>::push_back(const value_type&) [with _Tp = std::array<int, 4>; _Alloc = std::allocator<std::array<int, 4> >; std::vector<_Tp, _Alloc>::value_type = std::array<int, 4>]'
 1184 |       push_back(const value_type& __x)
      |       ^~~~~~~~~
/usr/include/c++/9/bits/stl_vector.h:1184:35: note:   no known conversion for argument 1 from '<brace-enclosed initializer list>' to 'const value_type&' {aka 'const std::array<int, 4>&'}
 1184 |       push_back(const value_type& __x)
      |                 ~~~~~~~~~~~~~~~~~~^~~
/usr/include/c++/9/bits/stl_vector.h:1200:7: note: candidate: 'void std::vector<_Tp, _Alloc>::push_back(std::vector<_Tp, _Alloc>::value_type&&) [with _Tp = std::array<int, 4>; _Alloc = std::allocator<std::array<int, 4> >; std::vector<_Tp, _Alloc>::value_type = std::array<int, 4>]'
 1200 |       push_back(value_type&& __x)
      |       ^~~~~~~~~
/usr/include/c++/9/bits/stl_vector.h:1200:30: note:   no known conversion for argument 1 from '<brace-enclosed initializer list>' to 'std::vector<std::array<int, 4> >::value_type&&' {aka 'std::array<int, 4>&&'}
 1200 |       push_back(value_type&& __x)
      |                 ~~~~~~~~~~~~~^~~