70. 爬楼梯

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.

思想：斐波那契数列问

 

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