Compilare: main.cpp: In function 'int main()': main.cpp:20:21: 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(int i = 0;i < s1.size();++i) | ~~^~~~~~~~~~~ main.cpp:20:5: warning: this 'for' clause does not guard... [-Wmisleading-indentation] 20 | for(int i = 0;i < s1.size();++i) | ^~~ main.cpp:24:9: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'for' 24 | for(int i = 0;i < s2.size();++i) | ^~~ main.cpp:24:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 24 | for(int i = 0;i < s2.size();++i) | ~~^~~~~~~~~~~ main.cpp:28:25: 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(int i = 0;i < s3.size();++i) | ~~^~~~~~~~~~~