current position:Home>leetcode 2057. Smallest Index With Equal Value(python)

leetcode 2057. Smallest Index With Equal Value(python)

2022-01-31 02:05:46 Wang Daya

「 This is my participation 11 The fourth of the yuegengwen challenge 4 God , Check out the activity details :2021 One last more challenge

describe

Given a 0-indexed integer array nums, return the smallest index i of nums such that i mod 10 == nums[i], or -1 if such index does not exist.

x mod y denotes the remainder when x is divided by y.

Example 1:

Input: nums = [0,1,2]
Output: 0
Explanation: 
i=0: 0 mod 10 = 0 == nums[0].
i=1: 1 mod 10 = 1 == nums[1].
i=2: 2 mod 10 = 2 == nums[2].
All indices have i mod 10 == nums[i], so we return the smallest index 0.
 Copy code 

Example 2:

Input: nums = [4,3,2,1]
Output: 2
Explanation: 
i=0: 0 mod 10 = 0 != nums[0].
i=1: 1 mod 10 = 1 != nums[1].
i=2: 2 mod 10 = 2 == nums[2].
i=3: 3 mod 10 = 3 != nums[3].
2 is the only index which has i mod 10 == nums[i].
 Copy code 

Example 3:

Input: nums = [1,2,3,4,5,6,7,8,9,0]
Output: -1
Explanation: No index satisfies i mod 10 == nums[i].
 Copy code 

Example 4:

Input: nums = [2,1,3,5,2]
Output: 1
Explanation: 1 is the only index with i mod 10 == nums[i].
 Copy code 

Note:

1 <= nums.length <= 100
0 <= nums[i] <= 9
 Copy code 

analysis

According to the meaning , Is to give out one from 0 List of integers to start indexing nums , The title requires us to return the smallest index i , send i mod 10 == nums[i] establish , If there is no index that matches the meaning of the question , Then go straight back -1 .

x mod y Express x Divide y The remainder of .

It seems very difficult , It's actually a simple question , It's traversal range(len(nums)) Every index i , If i%10 == nums[i] Go straight back to i , Otherwise, the traversal ends and returns directly to -1 .

answer

class Solution(object):
    def smallestEqual(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        for i in range(len(nums)):
            if i%10 == nums[i]:
                return i
        return -1
        	      
		
 Copy code 

Running results

Runtime: 60 ms, faster than 100.00% of Python online submissions for Smallest Index With Equal Value.
Memory Usage: 13.5 MB, less than 100.00% of Python online submissions for Smallest Index With Equal Value.
 Copy code 

analysis

You can also use built-in functions next , Just one line of code .

answer

class Solution(object):
    def smallestEqual(self, nums):
        """
        :type nums: List[int]
        :rtype: int
        """
        return next((i for i, x in enumerate(nums) if i%10 == x), -1)
 Copy code 

Running results

Runtime: 52 ms, faster than 100.00% of Python online submissions for Smallest Index With Equal Value.
Memory Usage: 13.4 MB, less than 100.00% of Python online submissions for Smallest Index With Equal Value.
 Copy code 

Original link :leetcode.com/problems/sm…

Your support is my greatest motivation

copyright notice
author[Wang Daya],Please bring the original link to reprint, thank you.
https://en.pythonmana.com/2022/01/202201310205443990.html

Random recommended