Compilare: main.cpp: In function 'int main()': main.cpp:22:17: warning: unused variable 'a' [-Wunused-variable] int n,x,l,i,a,b,ans=0,j; ^ main.cpp:22:19: warning: unused variable 'b' [-Wunused-variable] int n,x,l,i,a,b,ans=0,j; ^ main.cpp:29:15: warning: unused variable 'sans' [-Wunused-variable] long long sans=0; ^~~~