697. 数组的度

题目地址：https://leetcode-cn.com/problems/degree-of-an-array/submissions/

代码地址：https://github.com/javartisan/edx-ds/blob/master/src/main/java/com/javartisan/leetcode/Solution697.java 

import java.util.Arrays ;

class Solution {
    
    
    
    public int findShortestSubArray(int[] nums) {
        
    
        int size = nums.length;
        int max=-1;
        for(int i =0;i<size ;i++){
            if(nums[i]>max){
                max=nums[i];
            }
        }
        
        int[][] mtx =new int[max+1][3];
        
        for(int i=0;i<size;i++){
            int value = nums[i];
            int index = i+1;
           int[] startEndCount = mtx[value];
            if(startEndCount[0]==0){
                startEndCount[0]=index;
            }else{
                startEndCount[1]=index;
            }
            startEndCount[2]= startEndCount[2]+1;
        }
        
        int maxCount=-1;
        int returnSize = 0;
        for(int i=0;i<max+1;i++){
            if(mtx[i][2]>maxCount){
                maxCount=mtx[i][2];
                returnSize = mtx[i][1]-mtx[i][0]+1;
            }else if(mtx[i][2]==maxCount&&(mtx[i][1]-mtx[i][0]+1)<returnSize){
               returnSize= mtx[i][1]-mtx[i][0]+1;
            }
        }
    
        
        return returnSize<=0?1:returnSize;
        
    }
    
}

　　

优化数组空间：

      // 优化数组的空间
      public int findShortestSubArray(int[] nums) {
         
         int min=Integer.MAX_VALUE;
         int max=Integer.MIN_VALUE;
         int size = nums.length;
         
         for(int i=0;i<size ; i++){
            max = Math.max(max,nums[i]);
            min = Math.min(min,nums[i]);
         }
         
         // 优化数组的使用空间
         int tabSize = max-min+1;
         int[][] mtx = new int[tabSize][3];
         
         for(int i=0;i<size;i++){
            int value = nums[i]-min;
            int index = i+1;
            int[] startEndCount = mtx[value];
            if(startEndCount[0]==0){
                startEndCount[0]=index;
            }else{
                startEndCount[1]=index;
            }
            startEndCount[2]= startEndCount[2]+1;
        }
        
        int maxCount=-1;
        int returnSize = 0;
        for(int i=0;i<tabSize;i++){
            if(mtx[i][2]>maxCount){
                maxCount=mtx[i][2];
                returnSize = mtx[i][1]-mtx[i][0]+1;
            }else if(mtx[i][2]==maxCount&&(mtx[i][1]-mtx[i][0]+1)<returnSize){
               returnSize= mtx[i][1]-mtx[i][0]+1;
            }
        }
    
        
        return returnSize<=0?1:returnSize;
     }