Leetcode-70 Climbing Stairs

#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?

题解：这道题属于动态规划的题，类似于斐波那契数列，所以采用非递归的方式来解。当楼梯只有一级时，显然只有一种方法,即f(1)=1；当楼梯有两级时，显然有两种方法,即f(2)=2；当楼梯有n级时，f(n) = f(n-1) + f(n-2)；

class Solution {
public:
int climbStairs(int n) {
if(n<=2)
{
return n;
}
int array[n+1]={0};
array[1]=1;
array[2]=2;
for(int i=3;i<=n;i++)
{
array[i]=array[i-1]+array[i-2];
}
return array
;
}
};