斐波那契数列_07

 public int fibonacci(int n) {
        if (n==1||n==0){
            return n;
        }else {
            return fibonacci(n-1) + fibonacci(n-2);
        }
    }

public int Fibonacci(int n) {
        int [] nums=new int[40];

        nums[0]=0;
        nums[1]=1;
        for (int i = 2; i <= n; i++) {
            nums[i]=nums[i-1]+nums[i-2];
        }
        return nums[n];
    }

public class Solution {
    public int Fibonacci(int n) {
        if(n == 0){
            return 0;
        }else if(n == 1){
            return 1;
        }
        int sum = 0;
        int two = 0;
        int one = 1;
        for(int i=2;i<=n;i++){
            sum = two + one;
            two = one;
            one = sum;
        }
        return sum;
    }
}

public int Fibonacci(int n) {
        if(n == 0){
            return 0;
        }else if(n == 1){
            return 1;
        }
        
       //用于存放n-1时候的值
        int sum=1;
        int one=0;
        for (int i = 2; i <= n; i++) {
            sum=sum+one;
            one=sum-one;
        }
        return sum;
    }