第5章例5-7

#include<stdio.h>
int x;
int f( );
int main(void)
{
	int a=1;

	x = a;
	a = f();
	{
		int b = 2;
		b = a + b;
		x = x + b;
	}
	printf("%d%d",a,x);

	return 0;
}
int f()
{
	int x=4;

	return x;
}