poi.cpp: In function 'int main()':
poi.cpp:35:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
35 | for(int j = 0; j < v.size(); j++)
| ~~^~~~~~~~~~
poi.cpp:42:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
42 | for(int i = 0; i < VV.size(); i++)
| ~~^~~~~~~~~~~
poi.cpp:43:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
43 | for(int j = 0; j < VV[i].size(); j++)
| ~~^~~~~~~~~~~~~~