Write Python code to compute the frequency of each number in the list `[1, 2, 2, 3, 3, 3, 4]`.

You can use a dictionary or collections.Counter to count occurrences. Here’s a simple implementation:

numbers = [1, 2, 2, 3, 3, 3, 4]

# Using a dictionary
freq = {}
for num in numbers:
    freq[num] = freq.get(num, 0) + 1
print(freq)

# Using Counter
from collections import Counter
freq2 = Counter(numbers)
print(freq2)

Both snippets output {1: 1, 2: 2, 3: 3, 4: 1}. The time complexity is O(n) and the space complexity is O(k) where k is the number of distinct elements.