大话数据结构—两栈共享空间（五）

1.两栈共享空间

public class TwoStackShare {

    private static final int MAX_SIZE = 10;
    private int top1 = -1;
    private int top2 = MAX_SIZE;
    private Object[] data;

    public void push(int stackNumber, Object element) {
        if (top1 + 1 == top2) {
            throw new RuntimeException("栈满");
        }
        if (stackNumber == 1) {
            data[++top1] = element;
        } else {
            data[--top2] = element;
        }
    }

    public Object pop(int stackNumber) {
        if (stackNumber == 1) {
            if (top1 == -1) {
                throw new RuntimeException("栈1空");
            }
            return data[top1--];
        } else {
            if (top2 == MAX_SIZE) {
                throw new RuntimeException("栈2空");
            }
            return data[top2++];
        }
    }
}