Compilare: main.cpp: In function 'int main()': main.cpp:34:15: warning: unused variable 'a' [-Wunused-variable] int l,c,i,a,b,j,ii,sa,sb; ^ main.cpp:34:17: warning: unused variable 'b' [-Wunused-variable] int l,c,i,a,b,j,ii,sa,sb; ^ main.cpp:35:9: warning: variable 'prev' set but not used [-Wunused-but-set-variable] int prev =-1; ^~~~