Perfect squares

class Solution:
    def numSquares(self, n: int) -> int:
        items = []
        i = 1
        while i * i < 10 ** 4:
            items.append(i * i)
            i += 1
        dp = [math.inf] * (n + 1)
        dp[0] = 0
        for i in range(len(items)):
            for j in range(items[i], n + 1):
                dp[j] = min(dp[j], dp[j - items[i]] + 1)

        return dp[n]

Perfect Squares

Given an integer n, return the least number of perfect square numbers that sum to n.

A perfect square is an integer that is the square of an integer; in other words, it is the product of some integer with itself. For example, 1, 4, 9, and 16 are perfect squares while 3 and 11 are not.

Example 1:

Input: n = 12
Output: 3
Explanation: 12 = 4 + 4 + 4.

Example 2:

Input: n = 13
Output: 2
Explanation: 13 = 4 + 9.

Constraints:

1 <= n <= 10⁴