C＋＋＋作業3

項目1:個人所得税計算機

#include <iostream>   
using namespace std;
int main( )
{
	double dSalary,dTax=0,dNetIncome=0,dValue; 
	cout<<"           （ ）：";
	cin>>dSalary;//            dTax     dNetIncome
	dValue=dSalary-3500;
	if(dValue<=0) dTax=0.0;
    else if(0<dValue&&dValue<=1500) dTax=dValue*0.03-0.0;
	else if(dValue<=4500)dTax=dValue*0.10-105.0;
	else if(dValue<=9000)dTax=dValue*0.20-555.0;
	else if(dValue<=35000)dTax=dValue*0.25-1005.0;
	else if(dValue<=55000)dTax=dValue*0.30-2755.0;
	else if(dValue<=80000)dTax=dValue*0.35-5505.0;
	else if(dValue>80000)dTax=dValue*0.45-13505.0;
    dNetIncome=dSalary-dTax;
	cout<<"           "<<dTax<<"  ，      "<<dNetIncome<<"  。
";
	cout<<"    ，    。    ！
";
 	return 0;
}

項目3:定期預金利息計算機

#include <iostream.h>   
void main()
{
	double money,interest,all;
	int code;
	cout<<"         !"<<endl;
	cout<<"       ：";
	cin>>money;
	cout<<"==========    =========="<<endl;
	cout<<"1. 3  
2. 6  
3.   
4.   
5.   
6.    "<<endl;
	cout<<"          ：";
	cin>>code;
	switch(code)
	{
	case 1:
		{
			interest=money*0.031*0.250;
			all=interest+money;
			break;
		}
	case 2:
		{
			interest=money*0.033*0.5;
			all=interest+money;		
			break;
			
		}
	case 3:
		{
			interest=money*0.035*1;
			all=interest+money;
			break;
		}
	case 4:
		{
			interest=money*0.044*2;
			all=interest+money;
			break;
		}
	case 5:
		{
			interest=money*0.05*3;
			all=interest+money;
			break;
		}
	case 6:
		{
			interest=money*0.055*5;
			all=interest+money;
			break;
		}
	}	
	cout<<"     ："<<interest<<" ,"<<"      "<<all<<" "<<endl;
	cout<<"      ，      ！"<<endl;
	
}

項目4:多分数セグメント関数評価

#include <iostream.h>
#include <cmath>   
void main()
{
	double x,y;
	cout<<"   x  ：";
	cin>>x;
	
	if (x<2) y=x;
	else if (x<6) y=x*x+1;
	else if (x<10) y=sqrt(x+1);
	else if (x>=10) y=1/(x+1);
	cout<<"y="<<y<<endl;
}