Question

请用C++：编写一个非递归函数fibonacci(n)计算第n个费波拉奇数。

Answer 1

#include <stdio.h>
int fibo(int n)
{
int a=0,b=1,c,i;
if(n<=1)
return n;
else
{
for(i=2;i<=n;i++)
{
c=a+b;
a=b;
b=c;
}
return c;
}
}
void main()
{
int n;
scanf("%d",&n);
printf("fibo(%d)=%d",n,fibo(n));
}

Answer 2

n不大的时候地推就好了
fibs[1000] = {} ; //存储斐波那契数
fibs[0] = fibs[1] = 1 ;
for ( int i = 2 ; i <= n ; i ++ )
fibs[i] = fibs[i - 1] + fibs[i - 2] ;
cout << fibs[n] << endl ;

Answer 3

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<time.h>
//#include<algorithm>
//using namespace std;
const int MAX=500;

int main()
{
int f[30]={0,1};
int i,n;
scanf("%d",&n);
for(i=2;i<=n;i++)
{
f[i]=f[i-1]+f[i-2];
}
printf("%d\n",f[n]);
return 0;
}

Answer 4

递归可变为迭代