Initial data commit

Task/Sorting-algorithms-Insertion-sort/UNIX-Shell/sorting-algorithms-insertion-sort.sh

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+#!/bin/bash
+
+# Sorting integers with insertion sort
+
+function  insertion_sort ()
+{
+    # input: unsorted integer array
+    # output:  sorted integer array (ascending)
+
+    # local variables
+    local -a arr         # array
+    local -i i           # integers
+    local -i j
+    local -i key
+    local -i prev
+    local -i leftval
+    local -i N          # size of array
+
+    arr=( $@ )    # copy args into array
+
+    N=${#arr[*]}  # arr extent
+    readonly N    # make const
+
+    # insertion sort
+    for (( i=1; i<$N; i++ ))  # c-style for loop
+    do
+	key=$((arr[$i]))      # current value
+	prev=$((arr[$i-1]))   # previous value
+	j=$i                  # current index
+	
+	while [ $j -gt 0 ]  && [ $key -lt $prev ]  # inner loop
+	do
+	    arr[$j]=$((arr[$j-1])) # shift
+	
+	    j=$(($j-1))            # decrement
+
+	    prev=$((arr[$j-1]))    # last value
+	
+	done
+	
+	arr[$j]=$(($key))          # insert key in proper order
+
+    done
+
+    echo ${arr[*]}                   # output sorted array
+}
+
+################
+function main ()
+{
+    # main script
+    declare -a sorted
+
+    # use a default if no cmdline list
+    if [ $# -eq 0 ]; then
+	arr=(10 8 20 100 -3 12 4 -5 32 0 1)
+    else
+	arr=($@) #cmdline list of ints
+    fi
+
+    echo
+    echo "original"
+    echo -e "\t ${arr[*]} \n"
+
+    sorted=($(insertion_sort ${arr[*]}))  # call function
+
+    echo
+    echo "sorted:"
+    echo -e "\t ${sorted[*]} \n"
+ }
+
+
+#script starts here
+# source or run
+if [[ "$0" == "bash" ]]; then # script is sourced
+    unset main
+else
+    main "$@"                 # call with cmdline args
+fi
+
+#END