Compilare: user.cpp: In function ‘int main()’: user.cpp:7:25: warning: unused variable ‘a’ [-Wunused-variable] long long n,v,sol=0,a,i,j; ^ user.cpp:7:29: warning: unused variable ‘j’ [-Wunused-variable] long long n,v,sol=0,a,i,j; ^ user.cpp:7:27: warning: ‘i’ may be used uninitialized in this function [-Wmaybe-uninitialized] long long n,v,sol=0,a,i,j; ^