C program for electricity bill

#include<iostream>
using namespace std;
#define cost1 0.60
#define cost2 0.80
#define cost3 0.90
#define min 50
#include<conio.h>
void main()
{
char name[10][20];
float amount[10];
int units[10],n;

cout<<"Enter Number of Customers: ";
cin>>n;

cout<<"Enter Names and Number of Units Consumed\n";
for(int i=0;i<n;i++)
{
cout<<"-------------------------\n";
cout<<"Enter Customer Name: ";
cin>>name[i];
cout<<"Enter Number of units= ";
cin>>units[i];
cout<<"-------------------------\n";

if(units[i]<=100)
{
amount[i]=(units[i]*cost1)+min;
}
else if(units[i]>100&&units[i]<=300)
{
amount[i]=(((units[i]-100)*(cost2))+(100*cost1))+min;

}
else if(units[i]>300)
{
amount[i]=(((units[i]-300)*(cost3))+(200*cost2)+(100*cost1))+min;
amount[i]=amount[i]+(amount[i]*(15.0/100.0));
}
}

cout<<"**************BILL**************\n";
cout<<"Name\t\t"<<"Units\t\t"<<"Amount\n";
for(int i=0;i<n;i++)
{
cout<<name[i]<<"\t\t"<<units[i]<<"\t\t"<<"Rs."<<amount[i];
cout<<"\n";
}
getch();
}