diff --git a/math_logic_dp/climbing_stairs.py b/math_logic_dp/climbing_stairs.py index 0b3f0b8..6a8a76c 100644 --- a/math_logic_dp/climbing_stairs.py +++ b/math_logic_dp/climbing_stairs.py @@ -1,2658 +1,56 @@ +''' +You are climbing a staircase. It takes n steps to reach the top. +Each time you can either climb 1 or 2 steps. +In how many distinct ways can you climb to the top? +''' + + +def climb_stairs_o2n(n: int) -> int: + if n == 0 or n == 1: + return 1 + return climb_stairs_o2n(n-1) + climb_stairs_o2n(n-2) +def helper(n: int, memo: dict[int, int]) -> int: + if n == 0 or n == 1: + return 1 + if n not in memo: + memo[n] = helper(n-1, memo) + helper(n-2, memo) + return memo[n] - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Page not found · GitHub - - - - +def climb_stairs_memoization(n: int) -> int: + memo = {} + return helper(n, memo) + - - - - - - - - - - - - - - - - - - - - - - - - - - +def climb_stairs_optimized(n: int) -> int: + if n == 0 or n == 1: + return 1 + prev, curr = 1, 1 + for i in range(2, n+1): + temp = curr + curr = prev + curr + prev = temp + return curr +def climb_stairs_tabulation(n: int) -> int: + if n == 0 or n == 1: + return 1 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
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- - +if __name__ == "__main__": + print(climb_stairs_o2n(4)) + print(climb_stairs_memoization(4)) + print(climb_stairs_optimized(4)) + print(climb_stairs_tabulation(4))