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 {
public int climbStairs(int n) {
if(n==0)
return 0;
if(n==1)
return 1;
if(n==2)
return 2;
int f1 = 1,f2 = 2;
int f = f1 + f2;
for(int i=3;i<=n;i++)
{
f = f1 + f2;
f1 = f2;
f2 = f;
}
return f;
}
}
