Added Bash solution for anagram-detection (mre#129)

problems/anagram-detection/anagram-detection-test.bash

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+set -Eeuo pipefail
+
+fail=false
+assert() {
+ if [[ "$(./anagram-detection.bash -c "$1" "$2")" != "$3" ]]; then
+ echo "expected '$2' got '$1'" >&2
+ fail=true
+ fi
+}
+
+assert 'AdnBndAndBdaBn' 'dAn' 4
+assert 'AbrAcadAbRa' 'cAda' 2
+
+if [[ $fail == true ]]; then
+ exit 1
+fi

problems/anagram-detection/anagram-detection.bash

@@ -0,0 +1,95 @@
+#!/usr/bin/env bash
+set -Eeuo pipefail
+
+count=false
+while (($# > 0)); do
+ case "$1" in
+ -c | --count) count=true ;;
+ --) shift && break ;;
+ *) break ;;
+ esac
+ shift
+done
+
+parent=${1:?missing required parent argument}
+child=${2:?missing required child argument}
+
+declare -Ar char_map=(
+ [a]=2
+ [b]=3
+ [c]=5
+ [d]=7
+ [e]=11
+ [f]=13
+ [g]=17
+ [h]=19
+ [i]=23
+ [j]=29
+ [k]=31
+ [l]=37
+ [m]=41
+ [n]=43
+ [o]=47
+ [p]=53
+ [q]=59
+ [r]=61
+ [s]=67
+ [t]=71
+ [u]=73
+ [v]=79
+ [w]=83
+ [x]=89
+ [y]=97
+ [z]=101
+ [A]=103
+ [B]=107
+ [C]=109
+ [D]=113
+ [E]=127
+ [F]=131
+ [G]=137
+ [H]=139
+ [I]=149
+ [J]=151
+ [K]=163
+ [L]=167
+ [M]=173
+ [N]=179
+ [O]=181
+ [P]=191
+ [Q]=193
+ [R]=197
+ [S]=199
+ [T]=211
+ [U]=223
+ [V]=227
+ [W]=229
+ [X]=233
+ [Y]=239
+ [Z]=241
+)
+
+hash() {
+ declare -i hash=1
+ while read -rn1 c; do
+ if [[ "$c" != '' ]]; then
+ hash=$((hash * ${char_map[$c]}))
+ fi
+ done <<<"$1"
+ echo $hash
+}
+
+child_hash=$(hash "$child")
+matches=()
+for ((start = 0; start < $((${#parent} - ${#child})); start++)); do
+ substring=${parent:$start:${#child}}
+ if [[ "$child_hash" == "$(hash "$substring")" ]]; then
+ matches+=("$substring")
+ fi
+done
+
+if [[ $count == true ]]; then
+ echo "${#matches[@]}"
+else
+ printf '%s\n' "${matches[@]}"
+fi