Since he was 40 years old, Grandpa Edward has celebrated all of his birthdays by using candles shaped in the digits from 0 to 9 to indicate his age. First, he bought the candles of numbers 0 and 4. He always kept the candles to use in future birthdays, and only bought a new candle when it was not possible to indicate his age with the current candles. For example, when he was 41, he bought the candle of number 1.

###### Image credit: Wikipedia Gustavo86 .

Today, Grandpa Edward is 85 years old. How many candles has he had to buy, to light up his birthday cake throughout the years?

Include the candles of numbers 4 and 0 in your count.

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