Given n balls . All of them are initially uncolored . You have to color the balls with two colors RED and BLUE such that there can be atmost 2 positions where a RED ball is touching BLUE ball or vice versa. You have to color all the balls.Find the number of ways in which balls can be colored.
Example 1:
Input: n = 1
Output: 2
Explanation: Possible ways to color are {{R},{B}}.
So the answer is 2 .
Example 2:
Input: n = 2
Output: 4
Explanation: Possible ways to color are
{{RB},{BR},{RR},{BB}}.So the answer is 4.
Your Task:
You dont need to read input or print anything. Complete the function noOfWays() which takes n as input parameter and returns the number of ways in which balls can be colored.
Expected Time Complexity: O(1)
Expected Auxiliary Space: O(1)
Constraints:
1<= n <=10^{5}

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