Compilare: main.cpp: In function 'std::vector<char> trim(std::vector<char>)': main.cpp:38:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 38 | for (int i=0;i<a.size();i++) | ~^~~~~~~~~ main.cpp: In function 'std::vector<char> sum(std::vector<char>, std::vector<char>)': main.cpp:56:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 56 | for (int i=0;i<b.size();i++) | ~^~~~~~~~~ main.cpp: In function 'std::vector<char> dif1(std::vector<char>)': main.cpp:74:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 74 | while (i < a.size()) | ~~^~~~~~~~~~