IF - ELSE LADDER :

If - Else Ladder :

There is another way of putting ifs together when multiple decisions
involved.

Syntax :
 
      if (condition 1)
             statement-1;
        else if (condition 2)
                statement-2;
           else if (condition 3)
                    statement-3;
               else if (condition n)
                        statement-n;
                     else
                          default-statement;
     statement-x;

Problem :

An electric power distribution company charges its domestic consumers
as follows :
                           Consumption Units                         Rates of charge

                                     0 – 200                                  Rs. 0.50 per unit
                                  201 – 200                                Rs. 100 plus Rs. 0.65 per unit
                                  401 – 400                                Rs. 230 plus Rs. 0.80 per unit
                               601 and above                          Rs. 390 plus Rs. 1.00 per unit

Program Code :

         main()
             {

              int units, custnum;
              float charges;
              prinrf(“ Enter CUSTOMER NO. and UNITS consumed\n);
              scanf(“%d %d”, &custnum, &units);
              if (units <=200)
                   charges = 0.5 * units;
             else if (units <= 400)
                   charges = 100 + 0.65 * (units – 200);
             else if (units <= 600)
                    charges = 230 + 0.8 * (units – 400);
             else
                    charges = 390 + (units – 600);
             printf(“\n\nCustomer No: %d: Charges = %.2f\n”,custom,charges);
}

Output:

                 Enter CUSTOMER NO. and UNITS consumed 101 150
             Customer No.101 charges = 75.00
             Enter CUSTOMER NO. and UNITS consumed 202 225
             Customer No.202 charges = 116.25
             Enter CUSTOMER NO. and UNITS consumed 303 375
             Customer No.303 charges = 213.75
             Enter CUSTOMER NO. and UNITS consumed 404 520
             Customer No.404 charges = 326.00
             Enter CUSTOMER NO. and UNITS consumed 505 625
             Customer No.505 charges = 415.00