Shell-Implemented Calculators

1 #!/bin/bash

2 #FUNCTION Calculator

3 #AUTHOR Wangbo

4 #DATE 2015-09-26

5

6

7 function Checknum ()

8 {

9 Expr + 0 &>/dev/null

10

Case $? Inch

12 0)

return $

14;;

15 *)

16

Read-t 50-p "Please input integer:" int

18

Check "$int"

20

Return "$int"

22

23;;

Esac

25}

26

function operate ()

28 {

echo "$"

If ["$" = = "+"]

Then

echo "$ (($1$2$3))"

-Fi

If ["$" = "-"]

Then

echo "$ (($1$2$3))"

Panax Notoginseng fi

If ["$" = "*"]

About

echo "DDD"

echo "$ (($1$2$3))"

Fi

If ["$" = = "/"]

Then

echo "$ (($1$2$3))"

-Fi

47}

48

#get first number from user

Read-t 50-p "Please input first number:" First

51

Checknum "$first"

53

#get First Number

Fnum=$?

56

Operate #get

Read-t 50-p "Please input first operate (+-*/):" Operate

59

#get second number from user

Read-t 50-p "Please input second number:" Second

62

Checknum "$second"

64

#get Second Number

Snum=$?

67

#print result

69

Operate $fnum $operate $snum

This article is from the Shell Implementation Calculator blog, so be sure to keep this source http://codekong.blog.51cto.com/10704076/1699616

Shell-Implemented Calculators