LeetCode 3550. Smallest Index With Digit Sum Equal to Index

weekly contest 450。

題目

https://leetcode.com/problems/smallest-index-with-digit-sum-equal-to-index/description/

解法

按題意模擬。

時間複雜度 O(N)。
空間複雜度 O(1)。

class Solution:
    def smallestIndex(self, nums: List[int]) -> int:
        for i, x in enumerate(nums):
            sm = sum(int(c) for c in str(x))
            # sm = 0
            # while x > 0:
            #     x, r = divmod(x, 10)
            #     sm += r
            if sm == i:
                return i

        return -1