c++作业2

#include <iostream.h>
#include<math.h>;
void main()
{
double x1,x2,y1,y2,d,q;
cout<<"输入x1，y1的值：";
cin>>x1>>y1;
cout<<"输入x2，y2的值：";
cin>>x2>>y2;
q=(x2-x1)*(x2-x1)+(y2-y1)*(y2-y1);
d=sqrt(q);
cout<<"两坐标的距离是："<<d<<"\n";
}

#include<iostream.h>
void main()
{
int x,y;
cout<<"输入x的值：";
cin>>x;
if(x>=1)
y=x-1;
else
y=-x+1;
cout<<"y的值为：";
cout<<y<<"\n";
}

#include<iostream.h>
void main()
{
int a,b,c;
cout<<"建设银行欢迎您！\n";
cout<<"请插入银行卡\n";
cout<<"请输入银行卡密码：";
cin>>a;
b=123456;
if(a==b)
{
cout<<"请选择您要办理的业务：1.查询 2.取款 3.存款 4.转账 0.退出\n";
cin>>c;
if(c==1)
cout<<"谢谢,您选择了1号查询查询业务请稍等\n";
else if(c==2)
cout<<"谢谢,您选择了2号取款业务请稍等\n";
else if(c==3)
cout<<"谢谢,您选择了3号存款业务请稍等\n";
else if(c==4)
cout<<"谢谢,您选择了4号转账业务请稍等\n";
else if(c=0)
cout<<"谢谢,您选择了0号退出，欢迎下次光临本行\n";
}
else
cout<<"密码错误！请重新输入！\n";
}