C Assignment (Electricity bill)

#include
#include
void main()
{
int a,b,c,d,e,f,g;
clrscr();
printf("enter your value");
scanf("%d",&a);
if(a<=100)
{
b=a*2;
printf("your bill is %d",b);
}
else if(100{
b=a-100;
c=100*2;
d=b*3;
e=c+d;
printf("your bill is %d",e);
}
else if(200{
b=a-200;
c=100*2;
d=100*3;
e=b*4;
f=c+d+e;
printf("your bill is %d",f);
}
else if(a>300)
{
b=a-300;
c=100*2;
d=100*3;
e=100*4;
f=b*5;
g=c+d+e+f;
printf("your bill is %d",g);
}
else
{
printf("enter value in no only");
}
getch();
}