Initial data commit

Task/Rock-paper-scissors/UNIX-Shell/rock-paper-scissors.sh

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+#!/bin/bash
+choices=(rock paper scissors)
+
+# comparison function, works like Perl
+# winner x y =  2 if y beats x, 1 if x beats 1, 0 if it's a tie
+winner() {
+  local left="$1" right="$2"
+  echo $(( (3 + left - right) % 3 ))
+}
+
+
+human_counts=(1 1 1)
+human_count=3
+computer_counts=(0 0 0)
+games=0 human=0 computer=0
+
+PS3="What do you throw? "
+while true; do
+  select choice in rock paper scissors quit; do
+    if [ -z "$choice" ]; then choice="$REPLY"; fi
+    if [ "$choice" = "quit" ]; then
+      break 2
+    fi
+    for (( h=0; h<${#choices[@]}; ++h )); do
+      if [ "${choices[h]}" = "$choice" ]; then
+        break
+      fi
+    done
+    if (( h < 3 )); then
+      break
+    fi
+    echo "Unrecognized choice.  Try again!"
+  done
+
+  let n=RANDOM%human_count
+  for (( c=0; c<${#human_counts[@]}; ++c )); do
+    let n-=${human_counts[c]}
+    if (( n < 0 )); then
+       break
+    fi
+  done
+  let computer_counts[c]+=1
+  echo
+  echo "You chose ${choices[h]^^}"
+  echo "I chose ${choices[c]^^}"
+  w="$(winner "$c" "$h")"
+  case "$w" in
+     2) echo "YOU WIN!"; let human+=1;;
+     0) echo "TIE!";;
+     1) echo "I WIN!"; let computer+=1;;
+     *) echo "winner returned weird result '$w'";;
+  esac
+  echo
+  let games+=1
+  (( human_counts[(h+1)%3]+=1, human_count+=1 ))
+done
+
+echo
+echo "We played $games games.  You won $human, and I won $computer."
+for (( i=0; i<3; ++i )); do
+  echo "You picked ${choices[i]} $(( human_counts[ (i+1)%3 ] - 1 )) times."
+  echo "I picked ${choices[i]} $(( computer_counts[i] )) times."
+done