Compilare: user.cpp: In function ‘int main()’: user.cpp:199:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i <= nr; i ++) ^ user.cpp:203:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(fr[j] > 1 && j != x % 10) ^ user.cpp:219:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i <= nr; i ++) ^ user.cpp:164:32: warning: unused variable ‘k’ [-Wunused-variable] unsigned long long nr = 0, k = 0, fr[11] = {0}, D = 1, v[11] = {0}; ^ user.cpp:196:24: warning: unused variable ‘b’ [-Wunused-variable] unsigned long long b = x; ^