Compilare: main.cpp: In function 'int main()': main.cpp:64:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 64 | for (int i=0; i<c.size(); i++){ | ~^~~~~~~~~ main.cpp:67:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 67 | if (i<a.size()) | ~^~~~~~~~~ main.cpp:70:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 70 | if (i+1==a.size()) | ~~~^~~~~~~~~~ main.cpp:76:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 76 | if (i<b.size()) | ~^~~~~~~~~ main.cpp:79:28: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 79 | if (i+1==b.size()) | ~~~^~~~~~~~~~ main.cpp:88:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 88 | if (i+1==c.size()){ | ~~~^~~~~~~~~~