1295. Find Numbers with Even Number of Digits

難度: Easy

類型: Array, Math

CPP程式下載: 1295.cpp

前情題要:

給一個整數的陣列, 回傳"偶數位數"的個數。

Given an array nums of integers, return how many of them contain an even number of digits.

 

Example 1:

Input: nums = [12,345,2,6,7896]
Output: 2
Explanation: 
12 contains 2 digits (even number of digits). 
345 contains 3 digits (odd number of digits). 
2 contains 1 digit (odd number of digits). 
6 contains 1 digit (odd number of digits). 
7896 contains 4 digits (even number of digits). 
Therefore only 12 and 7896 contain an even number of digits.

Example 2:

Input: nums = [555,901,482,1771]
Output: 1 
Explanation: 
Only 1771 contains an even number of digits.

 

Constraints:

• 1 <= nums.length <= 500
• 1 <= nums[i] <= 105

思考方式:

1. 一直除以十, 就能知道是幾位數(十進位)。

2. 每個數字檢查, 整個巡過一輪就知道偶數位數的個數了。

複雜度思考:

Time Complexity: O( max value: 5*N ) 

Space Complexity: O( x )

結果:

Runtime: 0 ms, Beats: 100%

Memory: 13.49 MB, Beats: 48.60%

Accepted

105 / 105 testcases passed

tendchen

submitted at Apr 30, 2025 13:33

Runtime

0ms

Beats100.00%

Analyze Complexity

Memory

13.49MB

Beats48.60%

Analyze Complexity