#!/bin/bash

# 4 ways to count 1 o 20

#method 1
for i in $(seq 1 20)
do
    echo "A $i"
done


#method 2
list=(1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20)
for i in ${list[@]}
do
    echo "B $i"
done

#method 3
for (( i=1; $i<=20; i=i+1 ))
do
    echo "C $i"
done

# method 4
i=1
while [ $i -le 20 ]
do
    echo "D $i"
    i=$(($i+1))
done