Package g2401_2500.s2485_find_the_pivot_integer

Class Solution

java.lang.Object
g2401_2500.s2485_find_the_pivot_integer.Solution
public class Solution extends java.lang.Object
2485 - Find the Pivot Integer.

Easy

Given a positive integer n, find the pivot integer x such that:

  • The sum of all elements between 1 and x inclusively equals the sum of all elements between x and n inclusively.

Return the pivot integer x. If no such integer exists, return -1. It is guaranteed that there will be at most one pivot index for the given input.

Example 1:

Input: n = 8

Output: 6

Explanation: 6 is the pivot integer since: 1 + 2 + 3 + 4 + 5 + 6 = 6 + 7 + 8 = 21.

Example 2:

Input: n = 1

Output: 1

Explanation: 1 is the pivot integer since: 1 = 1.

Example 3:

Input: n = 4

Output: -1

Explanation: It can be proved that no such integer exist.

Constraints:

  • 1 <= n <= 1000

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int
    pivotInteger(int n)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • pivotInteger

      public int pivotInteger(int n)