Compilare: main.cpp: In function 'void divisors(long long unsigned int)': main.cpp:43:74: warning: unused variable 'len' [-Wunused-variable] long long unsigned exponents[(int)sqrt(n)+1], bases[(int)sqrt(n)+1], len=0, i, j, k, card = 1, sum = 1, aux=1, aux2; ^~~ main.cpp:43:87: warning: unused variable 'k' [-Wunused-variable] long long unsigned exponents[(int)sqrt(n)+1], bases[(int)sqrt(n)+1], len=0, i, j, k, card = 1, sum = 1, aux=1, aux2; ^ main.cpp:43:109: warning: unused variable 'aux' [-Wunused-variable] long long unsigned exponents[(int)sqrt(n)+1], bases[(int)sqrt(n)+1], len=0, i, j, k, card = 1, sum = 1, aux=1, aux2; ^~~ main.cpp:43:116: warning: unused variable 'aux2' [-Wunused-variable] long long unsigned exponents[(int)sqrt(n)+1], bases[(int)sqrt(n)+1], len=0, i, j, k, card = 1, sum = 1, aux=1, aux2; ^~~~ main.cpp: In function 'void prime()': main.cpp:15:17: warning: iteration 999999 invokes undefined behavior [-Waggressive-loop-optimizations] if(aux[i] == 0) ~~~~~^ main.cpp:13:14: note: within this loop for(i=2;i<=N;i++) ^