Question

2177. Find Three Consecutive Integers That Sum to a Given Number

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Description

Given an integer num, return _three consecutive integers (as a sorted array)__ that sum to _num. If num cannot be expressed as the sum of three consecutive integers, return_ an empty array._

 

Example 1:

Input: num = 33
Output: [10,11,12]
Explanation: 33 can be expressed as 10 + 11 + 12 = 33.
10, 11, 12 are 3 consecutive integers, so we return [10, 11, 12].

Example 2:

Input: num = 4
Output: []
Explanation: There is no way to express 4 as the sum of 3 consecutive integers.

 

Constraints:

• 0 <= num <= 1015

Solutions

Solution 1

class Solution:
  def sumOfThree(self, num: int) -> List[int]:
    x, mod = divmod(num, 3)
    return [] if mod else [x - 1, x, x + 1]

class Solution {
  public long[] sumOfThree(long num) {
    if (num % 3 != 0) {
      return new long[] {};
    }
    long x = num / 3;
    return new long[] {x - 1, x, x + 1};
  }
}

class Solution {
public:
  vector<long long> sumOfThree(long long num) {
    if (num % 3) {
      return {};
    }
    long long x = num / 3;
    return {x - 1, x, x + 1};
  }
};

func sumOfThree(num int64) []int64 {
  if num%3 != 0 {
    return []int64{}
  }
  x := num / 3
  return []int64{x - 1, x, x + 1}
}

function sumOfThree(num: number): number[] {
  if (num % 3) {
    return [];
  }
  const x = Math.floor(num / 3);
  return [x - 1, x, x + 1];
}