tests/arith3.sub

RANDOM=42
(( dice[RANDOM%6+1 + RANDOM%6+1]++ ))
echo ${dice[5]}

(( ++dice[RANDOM%6+1 + RANDOM%6+1] ))
echo ${dice[6]}

v=4
DIND=20

(( dice[DIND%6 + 1]=v ))
echo ${dice[3]}

RANDOM=42

(( dice[RANDOM%6+1 + RANDOM%6+1]+=v ))
echo ${dice[5]}

(( dice[RANDOM%6+1 + RANDOM%6+1]-=v ))
echo ${dice[6]}

(( dice[RANDOM%6+1 + RANDOM%6+1]+=2 ))
echo ${dice[11]}

(( dice[RANDOM%6+1 + RANDOM%6+1]*=2 ))
echo ${dice[11]}

unset dice1 dice2
RANDOM=42

for i in {1..5000}; do ((dice1[$RANDOM%6+1 + $RANDOM%6+1]++)); done;
unset t; for i in ${dice1[@]}; do ((t+=i)); done; echo $t

foo="${dice1[@]}"

RANDOM=42

for i in {1..5000}; do ((dice2[RANDOM%6+1 + RANDOM%6+1]++)); done;
unset t; for i in ${dice2[@]}; do ((t+=i)); done; echo $t

bar="${dice2[@]}"

if [ "$foo" != "$bar" ]; then
	echo "random sequences differ"
fi