Compilare: main.cpp: In function 'int check(int)': main.cpp:24:21: warning: comparison of integer expressions of different signedness: 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare] 24 | if( s[i].size() >= len ) { | ~~~~~~~~~~~~^~~~~~ main.cpp:38:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 38 | for( j = len; j < s[i].size(); j++ ) { | ~~^~~~~~~~~~~~~ main.cpp:73:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 73 | for( j = len; j < s[i].size(); j++ ) { | ~~^~~~~~~~~~~~~