Compilare: main.cpp: In function 'void read()': main.cpp:50:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 50 | for ( int i = 1; i < euler.size(); i ++ ) | ~~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:60:24: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 60 | if ( muchii.size() != 2 * n - 2 ) | ~~~~~~~~~~~~~~^~~~~~~~~~~~ main.cpp:68:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare] 68 | for ( int i = 1; i < muchii.size() && ok == 0; i += 2 ) | ~~^~~~~~~~~~~~~~~ main.cpp:78:16: warning: statement has no effect [-Wunused-value] 78 | ok == 1; | ~~~^~~~