C++与面向对象技术-实验4-讲解

程序1：编写程序，利用循环语句找出100到1000之间所有含有7的数(例如，107、174等)，将结果显示在屏幕上，并且每行最多显示10个数。

#include<iostream>
using namespace std;
int main()
{
int g,s,b,cnt = 0;
for(int i=100;i<1000;i++)
{
g = i % 10;
b = i / 100;
s = i / 10 % 10 ;
if(g==7||b==7||s==7)
{
cnt++;
cout<<i<<" ";
if(cnt==10)
{
cout<<endl;
cnt = 0;
}
}
}
return 0;
}
程序2：实现下述程序。

你刚开始在一家商店从事销售工作，你的年收入包括基本工资
你目标是年薪30000元。

试编写一个程序，求出挣得30000元必须完成的最小销售量。

#include <iostream>
#include <iomanip>
using namespace std;
double GetMinSalesAmount(double target,double salary)
{
double commission = 0.0;
double salesamount = 0;
do
{
salesamount += 0.01;
if(salesamount>=10000.01)
commission = 5000*0.08 + 5000 * 0.10 + (salesamount - 10000) * 0.12;
else if(salesamount>=5000.01)
commission = 5000*0.08 + (salesamount - 5000) * 0.10;
else
commission = salesamount * 0.08;
}
while(commission<target-salary);
return salesamount;
}
int main()
{
const double TARGET = 30000;
const double SALARY = 5000;
double salesamount = GetMinSalesAmount(TARGET,SALARY);
cout<<"销售额达到";
cout<<setiosflags(ios::fixed)<<setprecision(2)<<salesamount<<"时，你一年才能挣到";
cout<<setprecision(2)<<TARGET<<endl;
}
程序3：程序提示用户输入年和月（假设可输入的最早的年份是1800年，1800年1月1日是星期三），然后在控制台上显示该月的日历如图所示。

请尝试使用自顶向下的程序设计方法。

#include <iostream>
using namespace std;
int isLeapYear(int year)
{
return (year%400==0 || year%4==0 && year%100!=0);
}
int getNumberOfDaysInMonth(int year,int month)
{
if(month==1 || month==3 || month==5 ||month==7|| month==8 || month==10 || month==12) return 31;
if(month==4 ||month==6||month==9 ||month==11)
return 30;
if(isLeapYear(year))
return 29;
else
return 28;
}
int getTotalNumberOfDays(int year,int month)
{
int total = 0,i;
for(i = 1800;i<year;i++)
{
if(isLeapYear(i))
total +=366;
else
total +=365;
}
for( i = 1;i<month;i++)
{
total +=getNumberOfDaysInMonth(year,i);
}
return total;
}
int getStartDay(int year,int month)
{
int startDay1800 = 3;
int totalNumberOfDays = getTotalNumberOfDays(year,month);
return (getTotalNumberOfDays(year,month) + startDay1800)%7; }
void printMonthBody(int year,int month)
{
int startDay=getStartDay(year,month),i;
for(i = 0;i<startDay;i++)
cout<<" ";
for(i = 0;i<getNumberOfDaysInMonth(year,month);i++)
{
if(i<9)
cout<<" "<<(i+1);
else
cout<<" "<<(i+1);
if((i+startDay+1)%7==0)
cout<<endl;
}
}
void printMonthName(int month)
{
switch(month)
{
case 1: cout<<"January";break;
case 2: cout<<"Febuary";break;
case 3: cout<<"March";break;
case 4: cout<<"April";break;
case 5: cout<<"May";break;
case 6: cout<<"June";break;
case 7: cout<<"July";break;
case 8: cout<<"August";break;
case 9: cout<<"September";break;
case 10: cout<<"October";break;
case 11: cout<<"November";break;
case 12: cout<<"December";break;
}
}
void printMonthTitle(int year,int month)
{
cout<<"-----------------------------"<<endl;
cout<<" ";
printMonthName(month);
cout<<" "<<year<<endl;
cout<<"-----------------------------"<<endl;
cout<<" SUN MON TUE WED THU FRI SAT"<<endl; }
void printMonth(int year,int month)
{
printMonthTitle(year,month);
printMonthBody(year,month);
}
int main()
{
int year,month;
cout<<"input year:";
cin>>year;
cout<<"input month in number between 1 and 12:";
cin>>month;
printMonth(year,month);
cout<<endl;
return 0;
}。