// A scoping example.
#include <iostream>
using namespace std;
void useLocal(); // function prototype
void useStaticLocal(); // function prototype
void useGlobal(); // function prototype
int x = 1; // global variable
int main()
{
cout << "global x in main is " << x << endl;
int x = 5; // local variable to main
cout << "local x in main's outer scope is " << x << endl;
{ // start new scope
int x = 7; // hides both x in outer scope and global x
cout << "local x in main's inner scope is " << x << endl;
} // end new scope
cout << "local x in main's outer scope is " << x << endl;
useLocal(); // useLocal has local x
useStaticLocal(); // useStaticLocal has static local x
useGlobal(); // useGlobal uses global x
useLocal(); // useLocal reinitializes its local x
useStaticLocal(); // static local x retains its prior value
useGlobal(); // global x also retains its prior value
cout << "\nlocal x in main is " << x << endl;
} // end main
// useLocal reinitializes local variable x during each call
void useLocal()
{
int x = 25; // initialized each time useLocal is called
cout << "\nlocal x is " << x << " on entering useLocal" << endl;
++x;
cout << "local x is " << x << " on exiting useLocal" << endl;
} // end function useLocal
// useStaticLocal initializes static local variable x only the
// first time the function is called; value of x is saved
// between calls to this function
void useStaticLocal()
{
static int x = 50; // initialized first time useStaticLocal is called
cout << "\nlocal static x is " << x << " on entering useStaticLocal"
<< endl;
++x;
cout << "local static x is " << x << " on exiting useStaticLocal"
<< endl;
} // end function useStaticLocal
// useGlobal modifies global variable x during each call
void useGlobal()
{
cout << "\nglobal x is " << x << " on entering useGlobal" << endl;
x *= 10;
cout << "global x is " << x << " on exiting useGlobal" << endl;
} // end function useGlobal
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