Program using linux Shell of my Course Operating System

A Linux Shell Programming Gist

Here all of mine code is from my course.
To help my classmate and to store my shell program to use from anywhere
i'm using this GIST.

Addition Subtraction Multiplication Divide

#!/bin/bash

#function to add two numbers
add()
{
	x=$1
	y=$2
	sum=`expr $x + $y`
	echo -e "Number entered by u are: $x and $y"
	echo "sum of $1 and $2 is $sum "
}

#function of substract two number
sub()
{
	x=$1
	y=$2
	sum=`expr $x - $y`
	echo -e "Number You Entered are: $x and $y"
	echo "Sum of $1 and $2 is $sum "
	
}

#function of multiply two number
mul()
{
	x=$1
	y=$2
	sum=`expr $x \* $y`
	echo -e "Number you entered are: $x and $y"
	echo "Sum of $1 and $2 is $sum "
}

#function of divide into two number
div()
{
	x=$1
	y=$2

	sum`expr $x / $y`
	echo -e "Number you entered are: $x and $y"
	echo "Sum of $1 and $2 is $sum "

}


# main scripti
echo -e  "1.Add\n2.Sub\n3.Mul\n4.Div"

echo "Enter first number"
read first
echo "Enter second number"
read sec

echo -n  "Enter a value to do an operation:"
read n

if [ $n -eq 1 ]; then
	add $first $sec

elif [ $n -eq 2 ]; then
	sub $first $sec

elif [ $n -eq 3 ]; then
	mul $first $sec

elif [ $n -eq 4 ]; then
	div $first $sec

else
	echo "Error"

fi

Counting Positive & Negative number from Array

#!/bin/bash

echo "Enter random number's"
read -a arr

length=${#arr[@]}

#initial value of positive and negative
pos=0
neg=0

for((i=0;i<length;i++))
do

        #checking that it's neg or not
        if((${arr[$i]}<0))
        then
                neg=`expr $[neg+1]`
        else
                pos=`expr $[pos+1]`
        fi
done

echo "Number of Negative number is: " $neg
echo "Number of Positive number is: " $pos

FCFS using CPP

#include <iostream>
using namespace std;

int main()
{
	
	int  at[10], bt[10], wt[10], tat[10];
	int n;
	float avgwt = 0, avgtat = 0;
	cout << "Input how many process" << endl;
	cin >> n;
	
	//taking burst time
	cout << "Enter burst time of each process sequentially" << endl;
	for( int i = 0; i < n; i++){
		cout << "For process " << i+1<< ": ";
		cin >> bt[i];
	} 
	

	//calculating waiting time
	wt[0]=0;
	for( int i = 1; i <n; i++){
		wt[i]=0;
		for( int j = 0; j < i; j++){
			wt[i] += bt[j];
		}
		//cout << "Waiting time: " << wt[i] << endl;
	}

	cout << "Process\tBurst Time\tWaiting time\tTurnAround Time" << endl;
	
	for(int i = 0; i < n; i++){
		avgwt += wt[i];
		tat[i] = bt[i] + wt[i];
		avgtat += tat[i];
		cout << "p"<<i+1<<"\t"<<bt[i]<<"\t\t\t"<<wt[i]<< "\t\t "<< tat[i]<<endl;
	}
	avgwt /= n;
	avgtat /= n;
	cout << "Average waiting time: " << avgwt << endl;
	
	return 0;	
}

Find Factorial

#!/bin/bash


echo "Enter a number to get the factorial: "
read n
fac=1

if (( fac < 0 ))
then
        echo "Factorial of a negative number doesn't exist."
else

        #4=3*3*1
        for((i=1;i<=n;i++))
        do
                fac=`expr $[fac*i]`
        done
        echo "Factorial of $n is: " $fac
fi

GradeCheckShell1.sh

#!/bin/bash
#number difference 10

echo "Enter a nubmer"
read n
m=`expr $n / 10`

case "$m" in
	8|9|10 ) echo "A+" ;;
	7 ) echo "A" ;;
	6 ) echo "B" ;;
	5 ) echo "fail" ;;
	* ) echo "wrong input"

esac

GradeCheckShell2.sh

#!/bin/bash
#number difference 5

echo "Enter a number to check grade"
read n

m=`expr $n / 5`

case $m in
	16 ) echo "A";;
	17) echo "A+";;
	15 ) echo "A-";;
	14 ) echo "B";;
	13 ) echo "B-";;
	12|11|10|9|8|7|6|5|4|3|2|1) echo "Fail";;
	*) echo "Wrong input"

esac

Leap year using shell

#!/bin/bash

echo "Enter a value to check Leap year or not"
read a

if [ `expr $a % 400` == 0 ]; then
        echo "$a is leap year"

elif [ `expr $a % 100` == 0 ]; then
        echo "$a is leap year"

elif [ `expr $a % 4` == 0 ]; then
        echo "$a is leap year"

else
        echo "$a is not Leap year"

fi

Linear Search

#!/bin/bash

#we'll be searching from this array a value
array=(1 2 3 4 5)

#this flag is to check the desire value is found or not
flag=0

#this var is used for taking the position of the desire value
pos=0


echo "Enter a value to search: "
read a

#we know the array size to i<5
for((i=0;i<5;i++))
do
        #checking if the entered value matched or not   
        if ((${array[$i]}==$a))
        then

        #if matched change the flag 0 to 1
        flag=`expr $[flag+1]`

        #storing the position
        pos=$i+1
        break
        fi
done

#if we got a value flag will be 1 and this if statement will execute the position
if (($flag==1))
then
        printf "The current position of the value is: %d\n" $[pos]
else
        echo "Not found"
fi

Linear Search User input

#!/bin/bash

echo "Don't press enter, input value with a single space every time."

read -a arr

echo "Length of the array: "  ${#arr[@]}

#storing the length of the array
length=${#arr[@]}

#echo "the length is: " $length
#for i in ${arr[@]}
#do
#	echo $i
#done

echo

echo "Enter a value to search: "
read a
flag=0
pos=0

for((i=0;i<length;i++))
do
	if ((${arr[$i]}==$a))
	then
	flag=`expr $[flag+1]`
	
	#storing the position
	pos=$i+1
	break
	fi
done

if (($flag==1))
then
	echo "The current position of the value is: " $[pos]
else
	echo "Not found"
fi

Making a script to Move, Copy of file and Folder

#!/bin/bash

echo "Only for doc, sh, txt, c, cpp file"
echo "Enter a file name: "
read f1

echo "Enter extension: "
read ex1

echo "Enter destination: "
read d1

echo "1. Move\n2. Copy\n3. Move folder\n4. Copy folder"
read choice

if [ $choice == 2 ]; then
        if [[ ($ex1 == 'doc') || ($ex1 == 'sh') ||( $ex1 == 'txt') || ($ex1 == 'c') || ($ex1 == 'cpp') ]]; then
                cp $f1.$ex1 $d1
        fi
elif [ $choice == 1 ]; then
        if [[ ($ex1 == 'doc') || ($ex1 == 'sh') ||( $ex1 == 'txt') || ($ex1 == 'c') || ($ex1 == 'cpp') ]]; then
                mv $f1.$ex1 $d1
        fi
elif [ $choice == 3 ]; then
        mv $f1 $d1

elif [ $choice == 4 ]; then
        cp -r $f1 $d1
fi

One Sided Triangle Print

#for Example
#1
#2 2
#3 3 3

#!/bin/bash

echo "Pyramid"
read x
for ((i=1;i<=x;i++))
do
        for ((j=1;j<=i;j++))
        do
        echo -n $i " "
        done
        echo
done

Prime or not?

#!/bin/bash

echo -n "Enter a number to check prime or not: "
read n
i=2

while [ $i -lt $n ]
do
        if [ `expr $n % $i` -eq 0 ]
        then
                echo "$n is not a prime number"
                echo "Cause it's divisible by $i"
                exit
        fi

        i=`expr $i+1`
done

echo "$n is a Prime number."

Print 1-10 using loop

***********while loop**********
#!/bin/bash

echo "Print 1-10 using While loop"

i=1
while [ $i -le 10 ]
do
        echo $i
        #i=$((i+1))
        i=`expr $i + 1`
done

************UNTILL LOOP*********
#!/bin/bash

echo "Untill loop"
i=1
until [ $i -gt 10 ]
do
        echo $i
        i=`expr $i + 1`
done

echo "Another loop"
a=0
until [ ! $a -lt 10 ]
do
        echo $a
        a=`expr $a + 1`
done

********FOR LOOP**********
#!/bin/bash

echo "For loop"

for ((i=1;i<=10;i++))
do
        echo $i
done
echo
echo

#used to get the list of that directory file
echo "Another forloop"
echo
for i in `ls`
do
        echo $i
done
echo
#different style for loop
echo "another for loop"
echo
for a in {1..10..2}
do
  echo $a
done

Pyramid

#!/bin/bash

makePyramid()
{
 #here $1 is the parameter you passed with the function
 n=$1;

 #outer loop is for printing number of rows in the pyramid
 for((i=1;i<=n;i++))
 do
        #this loop print spaces required
        for((k=i;k<=n;k++))
        do
                echo -ne " "
        done

        #this loop print part2 of the pyramid
        for((j=1;j<=i;j++))
        do
                echo -ne "*"
        done

        #this loop print part 2 of the pyramid
        for((z=1;z<i;z++))
        do
                echo -ne "*";
        done

        #this echo used for printing new line
        echo;
done
}

#change number according to your need
echo "Enter a value of pyramid"
read n
makePyramid $n

Star Printing

#!/bin/bash

echo "Star printing"

#fixed the value of a row
i=5

#Get value from user of a Column
read n

for ((j=1;j<=n;j++))
do
        for ((k=1;k<=i;k++))
        do
                echo -n  "* "
        done
        echo
done

Sum and Average from User input

#!/bin/bash

echo "Don't enter untill You've done with entering value with one space"
echo "Like: 2 3 4 1"

read -a arr

#storing the length of array
length=${#arr[@]}

#initial value of sum
sum=0

for((i=0;i<length;i++))
do
        #storing every array value into a temp variable to add with sum
        temp=${arr[$i]}
        sum=`expr $[sum+temp]`
done

avg=$(echo "$sum / $length" | bc -l)
echo "Sum: " $sum
echo "Average: " $avg

Triangle Shape using Shell Scripting

#this way
# 1   4   9   16
# 1   4   9
# 1   4
# 1
#it was increasing the way from 3+2=5+2=7+2=9 like this so y=3 and adding +2

#!/bin/bash

echo "Enter row number"
read a

for((i=1;i<=a;i++))
do
        x=1
        y=3
        for((j=a;j>=i;j--))
        do

                echo -n "$x "
                x=`expr $x + $y`
                y=`expr $y + 2`
        done
        echo

done

use of Break

#!/bin/bash
#when initialize get into 5, it will exit, doesn't matter the loop is done or not :D
echo "Break use"

a=1
while [ $a -le 10 ]
do
        echo $a
        a=`expr $a + 1`
        if [ $a -eq 5 ]
        then
            break
        fi
        
done

use Of continue

#!/bin/bash

echo "Continue"

a=1

while [ $a -le 10 ]
do

        #wil check if a = 5 else it will go 16, if 5 thn continue without printing the value.        
        if [  $a -eq 5 ];
        then
        a=`expr $a + 1`
        continue
        fi
        echo $a
        a=`expr $a + 1`
done

WhileLoopShellSeriesSum.sh

#!/bin/bash
#2+4+6+....+n

i="y"
while [ $i == "y" ]
do
sum=0
echo "Enter a value"
read n
m=2
	echo "Number series"
	while [ $m -le $n ]
	do

	echo "$m"

	sum=`expr $sum + $m`

	m=`expr $m + 2`

	done

	echo "Result:  $sum"

echo "wanna continue?? press y"
read i
if [ $i != "y" ]
then
	exit
fi

done