斐波那契数列

斐波那契数列

先上代码

public class Solution {
    public int Fibonacci(int n) {
        int a = 1;
        int b = 1;
        int sum = 0;
        int k = 2;
        if(n==1 ||n==2){
            return a;
        }
        while(k < n){
            k++;
            sum = a + b;
            a = b;
            b = sum;

        }
        return sum;
    }
}

一开始while语句里写的是k!=n，系统提示超时