我也不知道他是第几次c++作业——代码篇

项目2：本月有几天？

#include <iostream.h>

int main()

{

int a,b,c,d;

cin>>a>>b;

c=a/4;

d=a/400;

switch(b)

{

case 1:cout<<"31\n";break;

case 3:cout<<"31\n";break;

case 5:cout<<"31\n";break;

case 7:cout<<"31\n";break;

case 8:cout<<"31\n";break;

case 10:cout<<"31\n";break;

case 12:cout<<"31\n";break;

case 4:cout<<"30\n";break;

case 6:cout<<"30\n";break;

case 9:cout<<"30\n";break;

case 11:cout<<"30\n";break;

default:cout<<"你在逗我？\n";break;

case 2:{

if(c*4!=a||d*400!=a) cout<<"28\n";

else cout<<"29\n";

}

}

return 0;

}

项目3：定期存款利息计算器

#include <iostream.h>

int main()

{

int a,b;

double c;

cout<<"请输入存款金额：";cin>>a;

cout<<"======请输入存款日期======\n";

cout<<"1.3个月\n";

cout<<"2.6个月\n";

cout<<"3.一年\n";

cout<<"4.两年\n";

cout<<"5.三年\n";

cout<<"6.五年\n";

cout<<"请输入存款代号：";cin>>b;

switch (b)

{

case 1:c=0.031;break;

case 2:c=0.033;break;

case 3:c=0.035;break;

case 4:c=0.044;break;

case 5:c=0.05;break;

case 6:c=0.055;break;

}

cout<<"到期利息为"<<c*a<<"元，本息合计共"<<c*a+a<<"元\n";

return 0;

}

项目4：多分数段函数求值

#include <iostream.h>

#include <cmath>

int main()

{

double a,b,c;

cout<<"x=";cin>>a;

if(a<2) cout<<"y="<<a<<endl;

if(2<=a&&a<6) cout<<"y="<<a*a+1<<endl;

if(6<=a&&a<10)

{

b=sqrt(a+1);

cout<<"y="<<b<<endl;

}

if(10<=a)

{

c=a+1;

b=1/c;

cout<<"y="<<b<<endl;

}

}