LeetCode, leetcodeoj

LeetCode, leetcodeoj

Question:

You are climbing a stair case. It takesNSteps to reach to the top.

Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?

Ideas:

The arrival of the current step n is from the n-1 step to come or two steps from the N-2 step

Package dp; public class ClimbingStairs {public int climbStairs (int n) {int [] dp = new int [n + 1]; dp [0] = dp [1] = 1; for (int I = 2; I <= n; ++ I) {dp [I] = dp [I-1] + dp [I-2];} return dp [n];} public static void main (String [] args) {// TODO Auto-generated method stub ClimbingStairs c = new ClimbingStairs (); System. out. println (c. climbStairs (4 ));}}