状态:
step[1]=1;
step[2]=2;
step[i]=step[i-1]+step[i-2];
class Solution {
public:
int climbStairs(int n) {
int *step=new int[n+1];//动态创建数组
step[1]=1;
step[2]=2;
int i=3;
while (i<=n) {
step[i]=step[i-1]+step[i-2];
++i;
}
int res=step[n];
delete [] step;//释放内存
return res;
}
};