Shell scripting Exercises (12.11)

For an even number of 100 or less

Idea: 1. Define a variable x first

The range of 2.x is 0-50,x with an initial value of 1

3. And the value initial value is 0, each time the loop and the value is equal to itself +2*i

Method One:

Vim sum1.sh

#!/bin/bash

#written by Lizheng

#about sum

Sum=0

For x in {1..50}; Do

sum=$ (($sum +2* $x))

Done

echo "The sum is $sum"

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Method Two: seq is a fixed notation

Idea: 1. First define a variable i

2. Let the value of sum first start with the value of 0,i from 1 to 1001.

3. Let I equals a number to remove to 2 if equal to 0, is the number we want to let them add together can get the sum needed

Vim sum2.sh

#/bin/bash

#written by Lizheng

#about sum

Let sum=0

For I in $ (seq 1 100); Do

If [$[$i%2] = = 0]; Then

Let sum+= $i

Fi

Done

echo "The sum is $sum."

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Shell scripting Exercises (12.11)