Write a C++ Program for Electricity Board Charge

/*An electricity board charges the following rates to domestic
users to discourage large consumption of energy:
For the first 100 units - 40p per unit
For next 200 units - 50p per unit
Beyond 300 units - 60p per unit
All users are charged a minimum of Rs.500. If the total cost is
more than Rs.250.00 then an additional surcharge of 15% is added.
Write a program to read the names of users and number of units
consumed and print out the charges with names.*/

#include
#include
void main()
{
clrscr();
cout<<"\n\n\n\tElectricity Board Charges\n";
cout<<"\n\tTo Discourage Large Consumption of energy\n\n";



char name[20];
cout<<"\n\nEnter USER name :-";
cin>>name;

cout<<"\n\nEnter Number of Units Consumed:-";
float unit;
cin>>unit;

//MANIPULATION
float tc;
if(unit<=100)
tc=unit*0.40;
else if(unit<=300)
tc=unit*0.50;
else
tc=unit*0.60;


float surchase=0;
if(tc>250)
surchase=tc*0.15;

float total_cost;
total_cost = 500 + surchase + tc;

cout<<"\n\nYOUR BILL AMOUNT IS "<< total_cost;

getch();
}