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?

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