Local variable in C++

#include<iostream.h>
#include<conio.h>
main()
{
{
auto int a=1;
cout<<"\n A Value is :"<<a;
}

{
int a=10;
cout<<"\n A Value is :"<<a;
}

{
int a=100;
cout<<"\n A Value is :"<<a;
}
getch();
}