Selection Sort Shell Script

#!/bin/bash#!/bin/bash
# SCRIPT: selectionsort.sh
#
# LOGIC : Here, to sort the data in ascending order, the first element
# ARRAY[0] is compared with all the other elements till the end of the
# array. If it is greater than any other the elements then they are
# interchanged. So after the first iteration of the outer for loop
# smallest element will be placed at the first position. The same pro-
# cedure is repeated for the other elements too.
#
#####################################################################
#                      Define Functions Here                        #
#####################################################################

printnumbers()
{
echo ${ARRAY[*]}
}

swap()
{
temp=${ARRAY[$1]}

ARRAY[$1]=${ARRAY[$2]}

ARRAY[$2]=$temp
}

sortnumbers()
{
for ((i=0;i<count;i++))
do
min=$i
  for ((j=i+1;j<count;j++))
  do
     if [ ${ARRAY[j]} -lt ${ARRAY[min]} ]
     then
     min=$j
     fi
  done
  swap $i $min
done
}

#####################################################################
#                       Variable Initialization                     #
#####################################################################

echo "Enter Numbers to be Sorted : "

read -a ARRAY

count=${#ARRAY[@]}

#####################################################################
#                       Main Script Starts Here                     #
#####################################################################

echo "---------------------------------------------------------------"

echo "Numbers Before Sort:"

printnumbers

sortnumbers

echo "Numbers After Sort: "

printnumbers

echo "---------------------------------------------------------------"



OUTPUT:

[root@www blog]# sh selectionsort.sh
Enter Numbers to be Sorted :
34 76 -8 12 23 5 9 -2 88 41 62
---------------------------------------------------------------
Numbers Before Sort:
34 76 -8 12 23 5 9 -2 88 41 62
Numbers After Sort:
-8 -2 5 9 12 23 34 41 62 76 88
---------------------------------------------------------------

NOTE: If we complement the if condition in this program, it will give
out the sorted array in descending order.