Compilare: user.cpp: In function ‘long long int reg(char*)’: user.cpp:48:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(unsigned i = 0; i < b;) ^ user.cpp:84:48: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(str[i] >= '0' && str[i] <= '9' && i < b) ^ user.cpp: In function ‘int main()’: user.cpp:110:23: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘long long int’ [-Wformat=] printf("%d", reg(str)); ^ /tmp/ccm3FbLS.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.