Leetcode•Oct 20, 2026
Airplane Seat Assignment Probability
Hazrat Ali
Leetcode
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).
Solution
var nthPersonGetsNthSeat = function(n) {
if (n === 1) return 1.0;
return 0.5;
};