Ex_1_3_03.md

title	date	draft	tags	categories
算法4 Java解答 1.3.03	2019-02-22 07:36:03 +0800	false	JAVA	技术 归档

1.3.03

问题：

Suppose that a client performs an intermixed sequence of (stack) push and pop operations. The push operations put the integers 0 through 9 in order onto the stack; the pop operations print out the return values. Which of the following sequence(s) could not occur?

分析：

a. 4 3 2 1 0 9 8 7 6 5
b. 4 6 8 7 5 3 2 9 0 1
c. 2 5 6 7 4 8 9 3 1 0
d. 4 3 2 1 0 5 6 7 8 9
e. 1 2 3 4 5 6 9 8 7 0
f. 0 4 6 5 3 8 1 7 2 9
g. 1 4 7 9 8 6 5 3 0 2
h. 2 1 4 3 6 5 8 7 9 0

0 : 4 3 2 1 0 9 8 7 6 5
    4 3 2 1 0 9 8 7 6 5
1 : 4 6 8 7 5 3 2 9 0 1
    4 6 8 7 5 3 2 9 1 wrong sequence!
2 : 2 5 6 7 4 8 9 3 1 0
    2 5 6 7 4 8 9 3 1 0
3 : 4 3 2 1 0 5 6 7 8 9
    4 3 2 1 0 5 6 7 8 9
4 : 1 2 3 4 5 6 9 8 7 0
    1 2 3 4 5 6 9 8 7 0
5 : 0 4 6 5 3 8 1 7 2 9
    0 4 6 5 3 8 7 wrong sequence!
6 : 1 4 7 9 8 6 5 3 0 2
    1 4 7 9 8 6 5 3 2 wrong sequence!
7 : 2 1 4 3 6 5 8 7 9 0
    2 1 4 3 6 5 8 7 9 0

参考：