[剑指offer]斐波那契数列
思路:
实现:
递归:
public class Solution {
public int Fibonacci(int n) {
return Fibonaccis(n,0,1);
}
public static int Fibonaccis(int n,int num1,int num2){
if(n==0)return 0;
if(n==1)return num2;
else return Fibonaccis(n-1 , num2 , num1+num2 );
}
}
非递归:
public class Solution {
public int Fibonacci(int n) {
int n1=1;
int n2=1;
if(n<=0) return 0;
if(n==1||n==2)return 1;
while(n-- > 2){
n1+=n2;
n2=n1-n2;
}
return n1;
}
}