Climbing Stairs
You are climbing a staircase with n steps to reach the top Each time you can climb either 1 or 2 steps Return the number of distinct ways to climb to the top Example: n = 2 => 2 (1+1 or 2) Example: n = 3 => 3 (1+1+1, 1+2, 2+1)
Count the ways to reach the top when you can take 1 or 2 steps at a time. It looks like a brute-force recursion problem, but it's actually your first real dynamic programming question. Once you see the Fibonacci pattern hiding inside, a whole category of DP problems clicks into place.
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