Data commit

Task/Bulls-and-cows/UNIX-Shell/bulls-and-cows.sh

@@ -0,0 +1,150 @@
+#!/bin/bash
+
+rand() {
+  local min=${1:-0}
+  local max=${2:-32767}
+
+  [ ${min} -gt ${max} ] &&
+  min=$(( min ^ max )) &&
+  max=$(( min ^ max )) &&
+  min=$(( min ^ max ))
+
+  echo -n $(( ( $RANDOM % $max ) + $min ))
+}
+
+in_arr() {
+  local quandry="${1}"
+  shift
+  local arr=( $@ )
+  local i=''
+
+  for i in ${arr[*]}
+  do
+    [ "${quandry}" == "${i}" ] && return 0 && break
+  done
+
+  return 1
+}
+
+delete_at() {
+  local idx="$(( $1 + 1 ))"
+  shift
+  local arr=( "sentinel" $@ )
+
+  echo -n "${arr[@]:1:$(( idx - 1 ))} ${arr[@]:$((idx + 1)):$(( ${#arr[@]} - idx - 1))}"
+}
+
+delete_first() {
+  local meanie="${1}"
+  shift
+  local arr=( $@ )
+  local i=0
+
+  for (( i = 0; i < ${#arr[@]} ; i++ ))
+  do
+    [ "${arr[${i}]}" == "${meanie}" ] && arr=( $( delete_at ${i} ${arr[*]} ) )
+  done
+
+  echo -n "${arr[*]}"
+}
+
+to_arr() {
+  local string="${1}"
+  local arr=()
+
+  while [ "${#string}" -gt 0 ]
+  do
+    arr=( ${arr[*]} ${string:0:1} )
+    string="${string:1}"
+  done
+
+  echo -n "${arr[*]}"
+}
+
+choose_idx() {
+  local arr=( $@ )
+
+  echo -n "$( rand 0 $(( ${#arr[@]} - 1 )) )"
+}
+
+locate_bulls() {
+  local secret=( $( to_arr "${1}" ) )
+  local guess=( $( to_arr "${2}" ) )
+  local hits=()
+  local i=0
+
+  for (( i=0; i<4; i++ ))
+  do
+    [ "${secret[${i}]}" -eq "${guess[${i}]}" ] && hits=( ${hits[*]} ${i} )
+  done
+
+  echo -n "${hits[*]}"
+}
+
+bulls() {
+  local secret="${1}"
+  local guess="${2}"
+  local bulls=( $( locate_bulls "${secret}" "${guess}" ) )
+
+  echo -n "${#bulls[@]}"
+}
+
+cows() {
+  local secret=( $( to_arr "${1}" ) )
+  local guess=( $( to_arr "${2}" ) )
+  local bulls=( $( locate_bulls "${1}" "${2}" ) )
+  local hits=0
+  local i=''
+
+  # Avoid double-counting bulls
+  for i in ${bulls[*]}
+  do
+    secret=( $( delete_at ${i} ${secret[*]} ) )
+  done
+
+  # Process the guess against what's left of the secret
+  for i in ${guess[*]}
+  do
+    in_arr "${i}" ${secret[*]} &&
+    secret=( $( delete_first "${i}" ${secret[*]} ) ) &&
+    (( hits++ ))
+  done
+
+  echo -n ${hits}
+}
+
+malformed() {
+  local guess=( $( to_arr "${1}" ) )
+  local i=''
+
+  [ ${#guess[@]} -ne 4 ] &&
+  return 0
+
+  for i in ${guess[*]}
+  do
+    if ! in_arr ${i} 1 2 3 4 5 6 7 8 9
+    then
+      return 0
+      break
+    fi
+  done
+
+  return 1
+}
+
+candidates=( 1 2 3 4 5 6 7 8 9 )
+secret=''
+
+while [ "${#secret}" -lt 4 ]
+do
+  cidx=$( choose_idx ${candidates[*]} )
+  secret="${secret}${candidates[${cidx}]}"
+  candidates=( $(delete_at ${cidx} ${candidates[*]} ) )
+done
+
+while read -p "Enter a four-digit guess:  " guess
+do
+  malformed "${guess}" && echo "Malformed guess" && continue
+  [ "${guess}" == "${secret}" ] && echo "You win!" && exit
+  echo "Score: $( bulls "${secret}" "${guess}" ) Bulls, $( cows "${secret}" "${guess}" ) Cows"
+done