Linux Programming _shell script exercises

1, write the shell script, calculate the 1~100 and.

#! /bin/bashsum=0 for in 'seq1';  do        sum=$[$i +$sum]doneecho $sum

2, write the shell script, enter a number n and calculate the 1~n.

Requirement: If the number entered is less than 1, re-enter until the correct number is entered.

#! /bin/Bashn=0 while[$n-lt"1"]; DoRead-P"Please input a number:"N Donesum=0 forIinch`seq 1$n '; Do        sum=$[$i +$sum] DoneEcho$sum

3, write shell script, batch build user user_00, user_01...user_99.

Requirement: All users belong to the Users group.

#! /bin/bashgroupadd users for in 'seq -w0";  Do -Gusers user_0$i4done         

4, write Shell script, batch add user jsj01-jsj09, jsj10-jsj99.

#! /bin/bashfor ((i=1;i<; i++));  Do if (i<);  Then JSJ="jsj0$i"; Else JSJ="jsj$i"; fi Useradd $JSJ  Done

5, write the shell script, require the following function: When executing a program, this program will let the user choose Boy or girl, if the user enters B or B, it is shown: he is a boy; if the user enters G or G, it is displayed: he is a girl If it is a character other than b/b/g/g, it is displayed: I don ' t know.

#! /bin/bashecho -n your choice:read choicecase in[g,g]Echo  "She is a girl. " "  "He's a boy. " " ;; *)echo"I don t know. " " ;; Esac

6, write the shell script, implement the subtraction operation between the two variables.

#! /bin/Bashread-P"imput NUM1:"Aread-P"input num2:"Bread-P"input Operator:"o Case$oinch+) Let"res=a+b"Echo$res;;-) Let"Res=a-b"Echo$res;;/)awk'begin{printf%.2f\n ",'$a'/'$b'}';;*) Let"res=a*b"Echo$res;;Esac

Linux Programming _shell script exercises