[LeetCode164] Maximum Gap

Given an unsorted array, find the maximum difference between the successive elements in its sorted form.

Try to solve it in linear time/space.

Return 0 if the array contains less than 2 elements.

You may assume all elements in the array are non-negative integers and fit in the 32-bit signed integer range.

public int maximumGap(int[] nums) {
        if(nums.length <2) return 0;
        if(nums.length ==2) {
            return Math.abs(nums[0]-nums[1]);
        }
        int maxValue = nums[0];
        int minValue = nums[0];
        for(int i=1; i<nums.length; i++){
            maxValue = (maxValue> nums[i])? maxValue:nums[i];
            minValue = (minValue< nums[i])? minValue:nums[i];
        }
        int avGap = (maxValue-minValue) / (nums.length-1);
        int bucketCount = 0;
        if(avGap == 0){
            return maxValue-minValue;
        }else {
            bucketCount = (maxValue-minValue) / avGap;
        }
        //<min,max>, initiate map
        List<Node> bucketMap = new ArrayList<>();
        for(int i=0;i<=bucketCount;i++){
            bucketMap.add(new Node(Integer.MAX_VALUE, Integer.MIN_VALUE));
        }
        //every bucket min&max
        for(int i=0;i<nums.length;i++){
            int index = (nums[i]-minValue)/avGap;
            int tempMax = (bucketMap.get(index).max<nums[i])?nums[i]:bucketMap.get(index).max;
            int tempMin = (bucketMap.get(index).min>nums[i])?nums[i]:bucketMap.get(index).min;
            bucketMap.get(index).setValue(tempMin, tempMax);
//            bucketMap.add(index, new Node(tempMin, tempMax));
        }
        //find maximum
        int maxGap = 0;
        int maxLeft = bucketMap.get(0).max;
        for(int i=1;i<=bucketCount;i++){
            Node n1 = bucketMap.get(i);
            if(n1.min!=Integer.MAX_VALUE){
                maxGap = Math.max(maxGap, n1.min-maxLeft);
                maxLeft = n1.max;
            }
        }
        return maxGap;
    }
	class Node {
	    int min;
	    int max;
	    public Node(int min, int max){
	        this.min = min;
	        this.max = max;
	    }
	    public void setValue(int min,int max){
	        this.max = max;
	        this.min = min;
	    }
	}