Part 1: To create a shell script for execution in UNIX system, you need to follo
ID: 3677074 • Letter: P
Question
Part 1:
To create a shell script for execution in UNIX system, you need to follow three steps:
(1) Create a shell script file with an editor (vim,emacs,nona...)
e.g. $vim GetStarted.sh
(2) Type your script in the editor and remember that the first line should declare which kind of shell this script is based on.
e.g. #!/bin/bash
(3) Save the file and change permission type so is can be executable.
e.g. $chmod +x GetStarted.sh
(4) In the current directory, execute the shell script.
e.g. $./GetStarted.sh
Now write a bash script (GetStarted.sh) to accept your first name as an argument and display the success information. The output could be like this.
$./GetStarted.sh Bing
Congratulations, Bing! You already known how to get started with shell script.
Part 2:
Here is the definition of Fibonacci numbers (from Wikipedia):
In mathematics, the Fibonacci numbers or Fibonacci series or Fibonacci sequence are the numbers in the following integer sequence:
0, 1, 1, 2, 3, 5, 8, 13 ...
By definition, the first two numbers in the Fibonacci sequence are 0 and 1, and each subsequent number is the sum of the previous two.
In mathematical terms, the sequence Fn of Fibonacci numbers is defined by the recurrence relation
Fn = Fn-1 + Fn-2 with seed values F0 =0,F1 =1.
Write a bash script (fib_lastname.sh) calculating Fibonacci number. It takes one argument n (n >= 0). Do not try numbers greater than 13, which may not work correctly due to number range limitation. The output looks like:
$./fib_li.sh 8 fib 8 = 21
$./fib_li.sh 10 fib 10=55
Explanation / Answer
Part1:
GetStarted.sh
#!/bin/bash
echo 'Congratulation,' $1'!'
//
Output:
:~/Desktop$ ./GetStarted.sh Bing
Congratulation, Bing!
Part2:
#!/bin/bash
function fib(){
if [ $1 -le 0 ]; then
echo 0
elif [ $1 -eq 1 ]; then
echo 1
else
echo $[`fib $[$1-2]` + `fib $[$1 - 1]` ]
fi
}
echo 'fib' $1 '=' `fib $1`
//
Output:
:~/Desktop$ ./fib_alex.sh 8
fib 8 = 21