Split Array into Consecutive Subsequences

You are given an integer array sorted in ascending order (may contain duplicates), you need to split them into several subsequences, where each subsequences consist of at least 3 consecutive integers. Return whether you can make such a split.

Example 1:

Input: [1,2,3,3,4,5]
Output: True
Explanation:
You can split them into two consecutive subsequences :
1, 2, 3
3, 4, 5

Example 2:

Input: [1,2,3,3,4,4,5,5]
Output: True
Explanation:
You can split them into two consecutive subsequences :
1, 2, 3, 4, 5
3, 4, 5

Example 3:

Input: [1,2,3,4,4,5]
Output: False

Note:

The length of the input is in range of [1, 10000]

public boolean isPossible(int[] nums) {
if(nums == null || nums.length == 0) return false;
List<int[]> list = new ArrayList<>();
for(int item: nums) {
if(list.size() == 0){
int[] add = new int[]{item, 1};
list.add(add);
}
else {
boolean canAdd = false;
for(int i=list.size()-1; i>=0;i--) {
int[] cur = list.get(i);

if(cur[0] + 1 == item) {
cur[0] = item;
cur[1] += 1;
canAdd = true;
break;
}
}
if(!canAdd) list.add(new int[]{item, 1});
}
}

for(int[] item: list) {
if(item[1] < 3) return false;
}
return true;
}

用到一个数组，用于记录当前这个subsequence的长度以及最大值。 每次遇到新的值，需要到这个数组里去匹配，看是否能够连接到某个串上。但是这里需要用到一定的贪心，要从后往前循环，为的是让后产生的子串的尽量变长。

代码：