Original Code Taken from here:

http://www.tldp.org/LDP/abs/html/bashver2.html#EX79

The code in the above link displays 4 unique 13 cards hands. I've modified it to deal a hand unique 2 card hand to 2 different players, then deal 5 unique community cards as in Texas Holdem (3 cards, then 1 card, then 1 card..)

However, I am finding that the DUPE_CHECK in the pick_a_card function and my deal_hole/deal_flop/deal_turn/deal_river is not work, hence, I'm getting non unique cards. I'm sure this is because it was previously going through all 52 cards and now I have it going through only 1-3 at a time, but I'm unsure of how to solve this problem. Any help would be appriciated:
Code:

#!/bin/bash

UNPICKED=0
PICKED=1

DUPE_CARD=99

LOWER_LIMIT=0
UPPER_LIMIT=51
CARDS_IN_SUIT=13
CARDS=52

declare -a Deck
declare -a Suits
declare -a Cards

initialize_Deck ()
{
i=$LOWER_LIMIT
until [ "$i" -gt $UPPER_LIMIT ]
do
  Deck[i]=$UNPICKED   # Set each card of "Deck" as unpicked.
  let "i += 1"
done
echo
}

initialize_Suits ()
{
Suits[0]=C #Clubs
Suits[1]=D #Diamonds
Suits[2]=H #Hearts
Suits[3]=S #Spades
}

initialize_Cards ()
{
Cards=(2 3 4 5 6 7 8 9 10 J Q K A)
}

pick_a_card ()
{
card_number=$RANDOM
let "card_number %= $CARDS"
if [ "${Deck[card_number]}" -eq $UNPICKED ]
then
  Deck[card_number]=$PICKED
  return $card_number
else  
  return $DUPE_CARD
fi
}

parse_card ()
{
number=$1
let "suit_number = number / CARDS_IN_SUIT"
suit=${Suits[suit_number]}
echo -n "$suit-"
let "card_no = number % CARDS_IN_SUIT"
Card=${Cards[card_no]}
printf %-4s $Card
}

seed_random ()  
{               
seed=`eval date +%s`
let "seed %= 32766"
RANDOM=$seed
}

deal_hole ()
{
echo

cards_picked=0
while [ "$cards_picked" -le 1 ]
do
  pick_a_card
  t=$?

  if [ "$t" -ne $DUPE_CARD ]
  then
    parse_card $t

    u=$cards_picked+1
    let "u %= $CARDS_IN_SUIT"
    if [ "$u" -eq 0 ]   
    then
     echo
     echo
    fi
    
    let "cards_picked += 1"
    fi  
done  
}

deal_flop ()
{
echo

cards_picked=0
while [ "$cards_picked" -le 2 ]
do
  pick_a_card
  t=$?

  if [ "$t" -ne $DUPE_CARD ]
  then
    parse_card $t

    u=$cards_picked+1
    let "u %= $CARDS_IN_SUIT"
    if [ "$u" -eq 0 ]   
    then
     echo
     echo
    fi
    
    let "cards_picked += 1"
    fi  
done  
}

deal_turn ()
{
echo

cards_picked=0
while [ "$cards_picked" -le 0 ]
do
  pick_a_card
  t=$?

  if [ "$t" -ne $DUPE_CARD ]
  then
    parse_card $t

    u=$cards_picked+1
    let "u %= $CARDS_IN_SUIT"
    if [ "$u" -eq 0 ]   
    then
     echo
     echo
    fi
    
    let "cards_picked += 1"
    fi  
done  
}

deal_river ()
{
echo

cards_picked=0
while [ "$cards_picked" -le 0 ]
do
  pick_a_card
  t=$?

  if [ "$t" -ne $DUPE_CARD ]
  then
    parse_card $t

    u=$cards_picked+1
    let "u %= $CARDS_IN_SUIT"
    if [ "$u" -eq 0 ]   
    then
     echo
     echo
    fi
    
    let "cards_picked += 1"
    fi  
done  
}
####
seed_random
initialize_Deck
initialize_Suits
initialize_Cards
player1hand=`deal_hole`
player2hand=`deal_hole`
flop=`deal_flop`
turn=`deal_turn`
river=`deal_river`

clear

echo -n "What is player 1's name? "; read player1
echo -n "What is player 2's name? "; read player2

echo "$player1hand"
echo "$player2hand"
echo "$flop"
clear
echo "$flop $turn"
clear
echo "$flop $turn $river"

echo "$player1's hand was $player1hand and $player2's hand was $player2hand"

exit 0