shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:39:19: error: 'abs' was not declared in this scope
39 | same_size[abs(shoes[i])].push_back({shoes[i], i});
| ^~~
shoes.cpp:45:9: error: 'sort' was not declared in this scope; did you mean 'short'?
45 | sort(same_size[i].begin(), same_size[i].end());
| ^~~~
| short
shoes.cpp:60:5: error: 'sort' was not declared in this scope; did you mean 'short'?
60 | sort(matchings.begin(), matchings.end());
| ^~~~
| short
shoes.cpp:64:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
64 | for (int i = 0; i < matchings.size(); i++) {
| ~~^~~~~~~~~~~~~~~~~~