Climbing Stairs

You are climbing a stair case. It takes n steps 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? Note: Given n will be a positive integer.

难度：easy

Solution: Dynamic Programming

public class Solution {
    public int climbStairs(int n) {
        int[] dp = new int[n + 1];
        dp[0] = 1;
        dp[1] = 1;
        for(int i = 2; i <= n; ++i) {
            dp[i] = dp[i - 1] + dp[i - 2];
        }

        return dp[n];
    }
}