Compilare: user.cpp: In function ‘int main()’: user.cpp:36:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<s.size()-1;i++) ^ user.cpp:81:14: warning: unused variable ‘x’ [-Wunused-variable] char x,y,z; ^ user.cpp:81:16: warning: unused variable ‘y’ [-Wunused-variable] char x,y,z; ^ user.cpp:81:18: warning: unused variable ‘z’ [-Wunused-variable] char x,y,z; ^ user.cpp:67:9: warning: ‘ok’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(ok==2) ^