软件工程概论 购书最低价格问题

#include <iostream>
using namespace std;

void main()
{
    int n;
    int i;
    cout<<"请输入本数："<<endl; 
    cin>>n;

    i = n/5;

    if(n<5)
    {
        if(n==1)  cout<<"最低价格为8元"<<endl;
        if(n==2)  cout<<"最低价格为"<<n*8*0.95<< "元"<<endl;
        if(n==3)  cout<<"最低价格为"<<n*8*0.9<< "元"<<endl;
        if(n==4)  cout<<"最低价格为"<<n*8*0.8<< "元"<<endl;
    }
    else
    {
        if(n%5==0)
        {
            cout<<i<<"套5本的"<<endl;
            cout<<"最低价格为："<<i*8*5*0.75<< endl;
        }
        if(n%5==1)
        {
            cout<<i<<"套5本"<<endl;
            cout<<"加"<<n%5<<"本"<<endl;
            cout<<"最低价格为："<<i*8*5*0.75+(n%5)*8<<endl;
        }
        if(n%5==2)
        {
            cout<<i<<"套5本"<<endl;
            cout<<"加"<<n%5<<"本"<<endl;
            cout<<"最低价格为："<<i*8*5*0.75+(n%5)*8*0.95<<endl;
        }
        if(n%5==3)
        {
            cout<<i-1<<"套5本的"<<endl;
            cout<<"加2套4本"<<endl;
            cout<<"最低价格为："<<(i-1)*8*5*0.75+2*4*8*0.8<<endl;
        }
        if(n%5==4)
        {
            cout<<i<<"套5本"<<endl;
            cout<<"加"<<n%5<<"本"<<endl;
            cout<<"最低价格为："<<i*8*5*0.75 +(n%5)*8*0.8<<endl;
        }
    }
}