Package g1201_1300.s1227_airplane_seat_assignment_probability

Class Solution

java.lang.Object
g1201_1300.s1227_airplane_seat_assignment_probability.Solution
public class Solution extends java.lang.Object
1227 - Airplane Seat Assignment Probability.

Medium

n passengers board an airplane with exactly n seats. The first passenger has lost the ticket and picks a seat randomly. But after that, the rest of the passengers will:

  • Take their own seat if it is still available, and
  • Pick other seats randomly when they find their seat occupied

Return the probability that the nth person gets his own seat.

Example 1:

Input: n = 1

Output: 1.00000

Explanation: The first person can only get the first seat.

Example 2:

Input: n = 2

Output: 0.50000

Explanation: The second person has a probability of 0.5 to get the second seat (when first person gets the first seat).

Constraints:

  • 1 <= n <= 105

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    double
    nthPersonGetsNthSeat(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

    • nthPersonGetsNthSeat

      public double nthPersonGetsNthSeat(int n)