Compilare: user.cpp: In function ‘long long unsigned int ndiv(long long int)’: user.cpp:17:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(p[i]*p[i]<=x && i<=z) ^ user.cpp:17:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(p[i]*p[i]<=x && i<=z) ^ user.cpp: In function ‘int main()’: user.cpp:40:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1; i<=n; i++) ^ user.cpp: In function ‘long long unsigned int sumdiv(long long unsigned int)’: user.cpp:78:40: warning: unused variable ‘j’ [-Wunused-variable] unsigned long long sum=1,i=1,e,s=0,j; ^