Compilare: main.cpp: In function 'bool valid(int)': main.cpp:12:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 12 | for( int j = 0; j < s[i].size(); j++ ) { | ~~^~~~~~~~~~~~~ main.cpp: In function 'int cb()': main.cpp:45:12: warning: 'rez' may be used uninitialized [-Wmaybe-uninitialized] 45 | return rez; | ^~~ main.cpp:33:9: note: 'rez' was declared here 33 | int rez, st = 1, dr = 61; | ^~~