How to count duplicate values in an array

{% set valuesCars = ['bmw', 'mercedes', 'seat', 'porsche', 'seat', 'bmw', 'seat'] %}

{% set valuesIntegers = [27, 32, 36, 36, 27, 32, 32] %}

{% set counts = {} %}

{# Change valuesCars to valuesIntegers to output the integers #}
{% for value in valuesCars %}
    {% if counts[value] is not defined %}
        {% set counts = counts|merge({ (value): 1 }) %}
    {% else %}
        {% set counts = counts|merge({ (value): counts[value] + 1 }) %}
    {% endif %}
{% endfor %}

{% for key, count in counts %}
    {{ key }}: {{ count }}
{% endfor %}

For valuesCars I get the correct output:
bmw: 2
mercedes: 1
seat: 3
porsche: 1

For valuesIntegers I don't get the desired output. I get this:
0: 1
1: 1
2: 1
3: 1
4: 1
5: 1
6: 1

The desired output should be
27 : 2
32: 3
36 : 2

What am I'm missing here?

This is the solution:

Convert the numeric key value into a string key to avoid issues with numeric indices

{% set stringKey = 'value_' ~ value %}

This results in:

value_27
value_32
value_36
value_36
value_27
value_32
value_32

Check if the key exists and update its count, else set the count to 1

{% if attribute(valuesWithNewKey, stringKey) is defined %}
    {% set valuesWithNewKey = valuesWithNewKey|merge({ (stringKey): valuesWithNewKey[stringKey] + 1 }) %}
{% else %}
    {% set valuesWithNewKey = valuesWithNewKey|merge({ (stringKey): 1 }) %}
{% endif %}

Inside the for loop (value in valuesIntegers) when you print the stringKey and values you will get:

{% for value in valuesWithNewKey %}
    {{ value }}<br>
{% endfor %}

value_27 : 1
value_32 : 1
value_32 : 1
value_36 : 1
value_36 : 1
value_36 : 1
value_36 : 1
value_36 : 1
value_36 : 2
value_27 : 2
value_27 : 1
value_27 : 2
value_32 : 2
value_32 : 2
value_32 : 2
value_32 : 2
value_32 : 3
value_32 : 2

Outside the for loop (value in valuesIntegers) after, replacing the 'value_' it will result in the desired output 🙏 💪 🏆

{% for stringKey, count in valuesWithNewKey %}
   {{ stringKey|replace({'value_':''}) ~ ' : ' ~ count }}<br>
{% endfor %}

27 : 2
32 : 3
36 : 2

The whole code:

 {% set valuesIntegers = [27, 32, 36, 36, 27, 32, 32] %}
 {% set valuesWithNewKey = {} %}

{% for value in valuesIntegers %}
   {% set stringKey = 'value_' ~ value %}

   {% if attribute(valuesWithNewKey, stringKey) is defined %}
     {% set valuesWithNewKey = valuesWithNewKey|merge({ (stringKey): valuesWithNewKey[stringKey] + 1 }) %}
   {% else %}
     {% set valuesWithNewKey = valuesWithNewKey|merge({ (stringKey): 1 }) %}
   {% endif %}
{% endfor %}

{% for stringKey, count in valuesWithNewKey %}
   {{ stringKey|replace({'value_':''}) ~ ' : ' ~ count }}<br>
{% endfor %}