3 digit

#!/bin/bash

read i1
read i2
read i3

if (( i1 == i2 )) ; then
    echo -n "$i1, $i2"
    if (( i2 == i3 )) ; then
        echo "$i3"
        break
    fi
elif (( i1 == i3 )) ; then
    echo -n "$i1 $i3"
    if (( i3 == i2 )) ; then
        echo "$i3"
        break
    fi
elif (( i2 == i3 )) ; then
    echo -n "$i2 $i3"
fi