# A Shell program To Find The GCD | Linux

The given problem asked in fico placement interview round. Find the gcd of two given numbers using shell scripting

We are given two numbers A and B and now task is to find the Greatest Common divisor (gcd) of two given number using shell scripting .

Asked in interview : FICO**Example:**

Input25 15Output5

## CPP

`// Script for finding gcd of two number` `// echo is for printing the message ` `echo Enter two numbers with space in between` `// read for scanning` `read a b` `// Assigning the value of a to m` `m = $a` `// Condition checking if b greater than m` `// If yes the replace the value of m assign a new value` `if` `[ $b -lt $m ]` `then` `m = $b` `fi` `// In do while loop we are checking the gcd` `while` `[ $m -ne 0 ]` `do` `x = `expr $a % $m`` `y = `expr $b % $m`` `// If x and y both are 0 then we complete over` `// process and we print the gcd` `if` `[ $x -eq 0 -a $y -eq 0 ]` `then` `// Printing the greatest gcd of two given number` `echo gcd of $a and $b is $m` `break` `fi` `m = `expr $m - 1`` `done` |

The shell script for the above code is :

echo Enter two numbers with space in between read a b //reads numbers m=$a if [ $b -lt $m ] then m=$b fi while [ $m -ne 0 ] do x=`expr $a % $m` y=`expr $b % $m` if [ $x -eq 0 -a $y -eq 0 ] then echo gcd of $a and $b is $m break fi m=`expr $m - 1` done

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