1296

1296. Divide Array in Sets of K Consecutive Numbers (Medium)

Given an array of integers nums and a positive integer k, find whether it's possible to divide this array into sets of k consecutive numbers
Return True if its possible otherwise return False.

 

Example 1:

Input: nums = [1,2,3,3,4,4,5,6], k = 4
Output: true
Explanation: Array can be divided into [1,2,3,4] and [3,4,5,6].

Example 2:

Input: nums = [3,2,1,2,3,4,3,4,5,9,10,11], k = 3
Output: true
Explanation: Array can be divided into [1,2,3] , [2,3,4] , [3,4,5] and [9,10,11].

Example 3:

Input: nums = [3,3,2,2,1,1], k = 3
Output: true

Example 4:

Input: nums = [1,2,3,4], k = 3
Output: false
Explanation: Each array should be divided in subarrays of size 3.

 

Constraints:

• 1 <= nums.length <= 10^5
• 1 <= nums[i] <= 10^9
• 1 <= k <= nums.length

Note: This question is the same as 846: https://leetcode.com/problems/hand-of-straights/

Related Topics:
Array, Greedy

Similar Questions:

• Split Array into Consecutive Subsequences (Medium)

Solution 1.

// OJ: https://leetcode.com/problems/divide-array-in-sets-of-k-consecutive-numbers/
// Author: github.com/lzl124631x
// Time: O(NlogM + MK) where M is the number of unique numbers in `A`.
// Space: O(N)
class Solution {
public:
    bool isPossibleDivide(vector<int>& A, int k) {
        if (A.size() % k) return false;
        map<int, int> m;
        for (int n : A) ++m[n];
        for (auto &[n, cnt] : m) {
            if (cnt == 0) continue;
            for (int i = 1; i < k; ++i) {
                if (m.count(n + i) == 0 || m[n + i] < cnt) return false; 
                m[n + i] -= cnt;
            }
        }
        return true;
    }
};