linux 按数字大小排序,shell 实现三个数大小排序

linux 按数字大小排序,shell 实现三个数大小排序

想到shell跟C 有那么多不同，之前想到用shell 怎么实现C里面三个数的大小排序呢？

今天想了下，实练了下，还是不困难，虽然算法那么普通；不过有想法然后能根据自己学的东西把想法实现，还是蛮有意思的。

1 #!/bin/bash

2

3 tmp=0

4 echo "input the three number"

5 read -p "1:" a

6 read -p "2:" b

7 read -p "3:" c

8 if [ $a -gt $b ]

9 then

10 tmp=$a

11 a=$b

12 b=$tmp

13 fi

14 if [ $a -gt $c ]

15 then

16 tmp=$a

17 a=$c

18 c=$tmp

19 fi

20 if [ $b -gt $c ]

21 then

22 tmp=$b

23 b=$c

24 c=$tmp

25 fi

26 echo "the sorted number is : $a $b $c"

~自测：

Loong:/home/yee# sh -x compare.sh

+ tmp=0

+ echo 'input the three number'

input the three number

+ read -p 1: a

1:23

+ read -p 2: b

2:43

+ read -p 3: c

3:35

+ '[' 23 -gt 43 ']'

+ '[' 23 -gt 35 ']'

+ '[' 43 -gt 35 ']'

+ tmp=43

+ b=35

+ c=43

+ echo 'the sorted number is : 23 35 43'

the sorted number is : 23 35 43

Loong:/home/yee# sh -x compare.sh

+ tmp=0

+ echo 'input the three number'

input the three number

+ read -p 1: a

1:12

+ read -p 2: b

2:13

+ read -p 3: c

3:16

+ '[' 12 -gt 13 ']'

+ '[' 12 -gt 16 ']'

+ '[' 13 -gt 16 ']'

+ echo 'the sorted number is : 12 13 16'

the sorted number is : 12 13 16

Loong:/home/yee# sh -x compare.sh

+ tmp=0

+ echo 'input the three number'

input the three number

+ read -p 1: a

1:54

+ read -p 2: b

2:43

+ read -p 3: c

3:32

+ '[' 54 -gt 43 ']'

+ tmp=54

+ a=43

+ b=54

+ '[' 43 -gt 32 ']'

+ tmp=43

+ a=32

+ c=43

+ '[' 54 -gt 43 ']'

+ tmp=54

+ b=43

+ c=54

+ echo 'the sorted number is : 32 43 54'

the sorted number is : 32 43 54