考虑下面假设的编程语言中的程序，它允许全局变量和静态或动态范围的选择。
int i ;
program main ()
{
i = 10;
call f();
}
procedure f()
{
int i = 20;
call g ();
}
procedure g ()
{
print i;
}
设 x 是静态范围下打印的值，y 是动态范围下打印的值。那么，x 和 y 是
(A) x = 10, y = 10
(B) x = 20, y = 10
(C) x = 10, y = 20
(D) x = 20, y = 20答案： (C)
说明：静态范围：
int i ;
program main ()
{
i = 10;
call f();
}
procedure f()
{
int i = 20;
call g ();
}
procedure g ()
{
print i; //as i=20 is scoped only within f() so it will point to global i
}
So, 10 is printed
Dynamic scoping:
int i ;
program main ()
{
i = 10;
call f();
}
procedure f()
{
int i = 20; // here global scoped i is changed
call g ();
}
procedure g ()
{
print i; // global value changed so, i=20 printed
}
这个问题的测验
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