warmup_2_array_count9.py

# Given an array of ints, return the number of 9's in the array.

# array_count9([1, 2, 9]) → 1
# array_count9([1, 9, 9]) → 2
# array_count9([1, 9, 9, 3, 9]) → 3

# Solution 1:
def array_count9(nums):
    count = 0
    for n in nums:
        if n == 9:
            count += 1
    return count

# Soution 2:
def array_count9(nums):
    digit = 9
    return nums.count(digit)