Given a positive integer total_steps, determine the number of distinct sequences of moves to reach the top of a staircase with total_steps steps, where each move consists of climbing either 1 or 2 steps. Return the total number of distinct sequences.
Example 1
Input: 4
Output: 5
Explanation: Possible sequences: [1,1,1,1], [1,1,2], [1,2,1], [2,1,1], [2,2]
Example 2
Input: 5
Output: 8
Explanation: Possible sequences: [1,1,1,1,1], [1,1,1,2], [1,1,2,1], [1,2,1,1], [2,1,1,1], [1,2,2], [2,1,2], [2,2,1]
Constraints
Case 1
Input: 6
Expected: 13
Case 2
Input: 7
Expected: 21
Case 3
Input: 8
Expected: 34