[LeetCode] Top Interview 150 Problems Solving # 70 Climbing Stairs

Understanding the Problem A number is given as n. Imagine that only 1 or 2 steps could be taken at once to reach the number n. For instance, if the number is 4, there are 5 ways to reach number 4. n = 4 # ways to reach n 1, 1, 1, 1 # 1 2, 1, 1 # 2 1...