Problem of the Day

Problem:

A t-shirt can be considered to have four holes in it: one hole for the head, two for the arms, and one at the bottom for the body. The static method holes, given a number of shirts num, is intended to calculate the total number of holes in the those shirts. Which of these static methods works as intended?

1. 
   

   public static int holes(int num)
   {
       return num * 4;
   }

2. 
   

   public static int holes(int num)
   {
       if (num <= 0)
           return 0;
       else
           return 4 + holes(num - 1);
   }

3. 
   

   public static int holes(int num)
   {
       int holeCount = 0;
       for (int i = 0; i < num; i++)
           holeCount += 4;
       return holeCount;
   }

1. I only
2. I and II only
3. I and III only
4. I, II, and III

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