Summing Nested Json - ruby

Question

So, we have a json response like:
Link to Formatted Sample Json
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What I want to do is sum all the numbers contained in the response.
Ive tried iterating through all the nesting but I was only been able to do one section. Using:
#number = 0
json["C"]["1"]["1"].each do |key, val|
val.map do |x|
#number+=x
end
end
#=> 150
Any suggestions how I would do that same for json["C"]["1"]?

Answer 1

Based on the JSON, here's code that'll walk the hash:
hash = JSON.parse(json)
def sum_hash(h)
sum = 0
h.each do |k, v|
sum += v.is_a?(Hash) ? sum_hash(v) : v.first
end
sum
end
sum_hash(hash) # => 1964
The hash has to be walked, and each value inspected since it's irregular. If the value is another hash sum_hash calls itself with that sub-hash, which then begins walking the sub-hash received.
For each hash value that isn't a hash, the integer is retrieved from the array using first and added to sum. When the method exits it returns the current value of sum, so, once the hash has been descended into, successive sum values get added.
Reducing the JSON makes it a LOT easier to make sure the code is doing the right thing:
json = '
{
"C": {
"1": {
"1": {
"A": [1],
"B": [1]
},
"2": {
"A": [1],
"B": [1]
},
"Review 1": {
"A": [1]
},
"Review 2": {
"A": [1]
}
}
}
}
'
Running the above code with that says the sum is 6.