Compilare: main.cpp: In function 'void r4()': main.cpp:45:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 45 | for(int j=0; j<inaltimi[i].size(); j+=2){ | ~^~~~~~~~~~~~~~~~~~~ main.cpp:49:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 49 | for(int i=0; i<inaltimi[0].size(); i++) | ~^~~~~~~~~~~~~~~~~~~