Compilare: main.cpp: In function 'int quickselect(int, int, int)': main.cpp:12:9: warning: unused variable 'lg' [-Wunused-variable] 12 | int lg=r-l+1; | ^~ main.cpp: In function 'int main()': main.cpp:43:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 43 | while(poz<s.size()&&isdigit(s[poz])) | ~~~^~~~~~~~~