echo Enter two numbers with space in between read a b 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