Leetcode 1984. Minimum difference in student scores

subject

To give you one Subscript from 0 Start Array of integers for nums , among nums[i] It means the first one i A student's grade . I'll give you another integer k .

Select any... From the array k A student's grade , Make this k Between scores The highest and Lowest score Of Difference value achieve To minimize the .

Return possible Minimum difference .

Example 1

Input ：nums = [90], k = 1
Output ：0
explain ： elect 1 A student's grade , have only 1 Methods ：
[90] The difference between the highest score and the lowest score is 90 - 90 = 0
The smallest possible difference is 0

Example 2

Input ：nums = [9,4,1,7], k = 2
Output ：2
explain ： elect 2 A student's grade , Yes 6 Methods ：
[9,4,1,7] The difference between the highest score and the lowest score is 9 - 4 = 5
[9,4,1,7] The difference between the highest score and the lowest score is 9 - 1 = 8
[9,4,1,7] The difference between the highest score and the lowest score is 9 - 7 = 2
[9,4,1,7] The difference between the highest score and the lowest score is 4 - 1 = 3
[9,4,1,7] The difference between the highest score and the lowest score is 7 - 4 = 3
[9,4,1,7] The difference between the highest score and the lowest score is 7 - 1 = 6
The smallest possible difference is 2

Ideas

1. To find the minimum difference , Then the first thought should be sorting , We can use Arrays.sort Methods , Implement non descending arrangement .
2. After arranging the order , We according to the k value , Compare the differences in turn k The size of adjacent values of units .

Code

public static  int minimumDifference(int [] nums,int k){
    
        Arrays.sort(nums);
        int ans=nums[k-1]-nums[0];
        for(int i=k;i<nums.length;i++){
    
            ans=Math.min(ans,nums[i]-nums[i-k+1]);
        }
        return ans;
    }