tabletennis.cpp: In function 'int main()':
tabletennis.cpp:18:40: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
18 | if(vis[a[i] + a[j]].size() >= n / 2) num = a[i] + a[j];
| ~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~
tabletennis.cpp:23:20: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'll' {aka 'long long int'} [-Wsign-compare]
23 | while(v.size() < n && i < vis[num].size()) {
| ~~~~~~~~~^~~
tabletennis.cpp:23:29: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
23 | while(v.size() < n && i < vis[num].size()) {
| ~~^~~~~~~~~~~~~~~~~