Compilare: main.cpp: In function 'int main()': main.cpp:20:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 20 | for(i=1; i<a.size(); i++) | ~^~~~~~~~~ main.cpp:24:16: warning: suggest parentheses around assignment used as truth value [-Wparentheses] 24 | if(a[j]=a[i]) main.cpp:28:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 28 | for(i=j=0; i<b.size(); i++) | ~^~~~~~~~~ main.cpp:33:13: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 33 | if(j==a.size()) | ~^~~~~~~~~~