Compilare: main.cpp: In function 'int main()': main.cpp:26:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 1 ; i < s.size() ; ++ i ) { ~~^~~~~~~~~~ main.cpp:36:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0 ; i < t.size() ; ++ i ) { ~~^~~~~~~~~~ main.cpp:43:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( L == s.size() ) { ~~^~~~~~~~~~~