regions.cpp: In function 'int32_t main()':
regions.cpp:49:19: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
49 | for (int i=0;i<V.size();i++)
| ~^~~~~~~~~
regions.cpp:65:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
65 | for (int i=0;i<ve[r2].size();i++){
| ~^~~~~~~~~~~~~~
regions.cpp:66:21: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
66 | while (j<ve[r1].size()){
| ~^~~~~~~~~~~~~~
regions.cpp:35:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
35 | freopen("regions.in","r",stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
regions.cpp:36:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
36 | freopen("regions.out","w",stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~