斐波那契数(fibonacci number)

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/**************************************************************** 
 * Description: Fibonacci number
 * Author: Alex Li
 * Date: 2022-05-01 18:25:39
 * LastEditTime: 2024-06-10 21:58:21
****************************************************************/

#include <iostream>
using namespace std;

//空间优化
int fibonacciProcess(int n){
    int a = 0, b = 1, c, i;
    c=a+b;
    for(i = 3; i < n; i++){
       a = b;
       b = c;
       c=a+b;
    }
    return c;
}

int f[100];
//动态规划
int FibonacciTabulation(int n){
    f[0]=0;
    f[1]=1;
    for (int i = 0; i < n-2; i++)f[i+2]=f[i]+f[i+1];
    return f[n-1];
}

//递归
int FibonacciRecursion(int n){
    if(n==1)return 0;
    if(n==2)return 1;
    else return FibonacciRecursion(n-1)+FibonacciRecursion(n-2);
}

int main(){
    int n;
    cout<<"please input Fibonacci number:";
    cin>>n;
    cout<<fibonacciProcess(n)<<endl;
    cout<<FibonacciRecursion(n)<<endl;
    cout<<FibonacciTabulation(n)<<endl;
    for (int i = 0; i <n; i++){
        cout<<f[i]<<' ';
    }
    return 0;
}