I am getting a "bad substitution" error while running this code. I want to print the values in `h_1`, `h_2`, `h_3`with a `for` loop.

```
#/!/bin/bash
h_1=12
h_2=13
h_3=14
for ((i=1; i<=2; i++))
 do
  echo "${h_$i}"
done

```