#include<iostream>

using namespace std;

int main()
{
    int pound,p0,p1,days,result;
    char ans;
    
    do
    {
        cout<<"Please input the pound and the days:\n";
        cin>>pound>>days;
        
        int n = days/5;
        if(0 == n || 1 == n)
            {
                result = pound;
                cout<<"The result is "<<result<<endl;
            }
        else
            {
                result = 0;
                p0 = p1 = pound;
                for(int i = 1;i < n;i++)
                    {
                        result = p0 + p1;
                        p0 = p1;
                        p1 = result;
                    }
            cout<<"The result is "<<result<<endl;
            }
            
        cout<<"Do you want again?";
        cin>>ans;
    }while(‘y‘ == ans || ‘Y‘ == ans);
    
    
}

斐波那契计算绿锈。

Fibonacci