a-stack:一种用数组实现的栈结构 a_stack last :0..n (top of stack * n integer (max size * elements array [1..n]of elemtype (the elements in 请注意 the stack * elements的实 栈的形式规约： 现和规约的区别 stack c integer (current time-point * max integer (maximum allowable size * elems pair-set (elems is a set of pairs * pair :object elemtype (object is of type elemtype * t integer (t is a time-stamp *a-stack: 一种用数组实现的栈结构 栈的形式规约： 请注意 elements的实 现和规约的区别