题目
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.
分析
很简单的动态规划,通过分析能够得到,F(n)=F(n-1)+F(n-2)。然后通过简单的数组迭代就能得到结果。当然也可以利用Fibonacci数列的简便
int climbStairs(int n) {
if(n==0||n==1)return 1;
int a[1000000];
a[0]=1;
a[1]=1;
for(int i=2;i<=n;i++)
{
a[i]=a[i-1]+a[i-2];
}
return a[n];
}