70. 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.

public class Solution {
    int temp[] = new int[100];
    public int climbStairs(int n) {
        if(n<=1) return 1;
        if(temp[n] != 0) return temp[n];
        return temp[n] = climbStairs(n-1) + climbStairs(n-2);
    }
}