List of Top 3 Hills

Problem

　　There is a data which provides heights (in meter) of mountains. The data is only for ten mountains.

　　Write a program which prints heights of the top three mountains in descending order.

 

Input

　　Height of mountain 1
　　Height of mountain 2
　　Height of mountain 3
　　 .
　　 .
　　Height of mountain 10

Constraints

　　0 ≤ height of mountain (integer) ≤ 10,000

 

Output

　　Height of the 1st mountain
　　Height of the 2nd mountain
　　Height of the 3rd mountain

Sample Input 1

1819
2003
876
2840
1723
1673
3776
2848
1592
922

Output for the Sample Input 1

3776
2848
2840

Sample Input 2

100
200
300
400
500
600
700
800
900
900

Output for the Sample Input 2

900
900
800

  

 

 

题目大意

　　输入十座山的高度，依次输出前三高的高度。

 

题目解读

　　没仔细读题，当成了数量不定的若干座山来做。

 

算法

　　循环读入到文件结束，对于每一个数值，判断其是否高于当前存储的最大值，是则交换，再依次与次大、第三大值比较、交换，算法时间复杂度 O(N)。

 

代码

h1 = h2 = h3 = 0
while (1):
    try:
        h = int(input())
    except EOFError:
        break
    if (h1 < h):
        h1, h = h, h1
    if (h2 < h):
        h2, h = h, h2
    if (h3 < h):
        h3, h = h, h3
print(h1)
print(h2)
print(h3)

 

代码解读

　　注意：以下内容完全根据笔者自己对 Python 3 的理解胡说八道。

　　a, b = b, a：Python 3 的特殊的进行变量交换方式。