tabletennis.cpp: In function 'bool solve(int)':
tabletennis.cpp:29:26: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
29 | while(l<r&&ans.size()<n){
| ~~~~~~~~~~^~
tabletennis.cpp:37:18: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
37 | if(ans.size()==n)return 1;
| ~~~~~~~~~~^~~
tabletennis.cpp: In function 'int main()':
tabletennis.cpp:44:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
44 | freopen("test_input.txt", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tabletennis.cpp:45:8: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
45 | freopen("test_output.txt", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~