java – Checking for the last digit 9

Question:

Hello. In the course of work, I had to check whether the last digit of the number is nine. While wrote the crutch

if(("" + num).endsWith("9"))

How can you check mathematically? Range [0, 99]

Answer:

For example, like this:

Math.abs(n) % 10 == 9

If you know for sure that the number is positive, you don't have to evaluate Math.abs .

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