Count Distinct Ways to Reach the Nth Stairs

Consider a scenario where you have been given a number of stairs. You start at the 0th stair and need to reach the Nth stair. With each stride, you can choose to either ascend one step or two steps. Your task is to determine the number of distinct ways to move from the 0th to the Nth stair.

Input:

N = 3
Output:
3
Example:

The example scenarios could be:
- Climbing one step at a time: (0, 1), (1, 2), (2, 3)
- Climbing first two steps then one step: (0, 2), (2, 3)
- Climbing one step then two steps: (0, 1), (1, 3)

Constraints:

  • 1 <= T <= 100
  • 0 <= N <= 1018
Note:

You do not need to print anything; input and output handling are already managed. Simply implement the required logic in the function.

Sharan. Medamoni
5mo
public class Staircase { // Function to count the number of ways to reach the nth stair public static int countWays(int n) { if (n &lt;= 1) { return 1; } // Array to store the number of ways to reach ...read more
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