斐波那契数列求解,按照定义求解即可
C++ 代码
class Solution {
public:
int fib(int n) {
if(0 == n)return 0;
if(1 == n)return 1;
int a = 0, b = 1, res = 0;
for(int i=2; i<=n; ++i) {
res = a+b;
a = b, b = res;
}
return res;
}
};