haveThree challenge

I think it is inappropriate to post code or psuedo code on these homework-tyupe questions until the Asker has at least had a chance to respond to an initial hint.

prev_num=nums[i];  // Remember current num for next time through loop

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why we need to do this step? I was not clear on above step?Please advise

i got it now.
count3s.png

public class TestTwo {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		int[] ar = { 3, 1, 3, 2, 3,3 };
		System.out.println("value is-->" + haveThree(ar));
	}

	public static boolean haveThree(int[] nums) {
		int count = 0;
		int prev_num = 0;
		for (int i = 0; i < nums.length; i++) {
			// Increment count only if current num is 3 and previous num is not
			// 3
			if (nums[i] == 3 && prev_num != 3) {
				count++;
			}
			prev_num = nums[i]; // Remember current num for next time through
								// loop
		}
		return count == 3; // Returns "true" if count is 3, otherwise returns
							// false
	}

}

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above gave true which is wrong

public boolean haveThree(int[] nums) {
  int count=0;
  int prev_value=0;
 // boolean result=false;
  for(int i=0;i<nums.length;i++){
    if(nums[i]==3&&prev_value!=3){
      count++;
    }
    prev_value=nums[i];
  }
  return count==3;
}

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what is difference between above approach and below approach

public boolean haveThree(int[] nums) {
  int count=0;
  int prev_num=0;
  for(int i=0;i<nums.length;i++){
    if(nums[i]==3){
      count++;
      if(nums[i]==prev_num){
        count=9; // Just some non-3 number to signify failure
        break;   // Break out of loop.  Optional (just to save time looping through rest of elements for nothing)
      }
    }
    prev_num=nums[i];  // Remember current num for next time through loop
  }
  return count==3;  // Return true if count is 3, otherwise return false
}

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i see one aditional if loop for

if(nums[i]==prev_num){
		        count=9; // Just some non-3 number to signify failure
		        break;   // Break out of loop.  Optional (just to save time looping through rest of elements for nothing)
		      }

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to my eyes both above approaches are same. please advise

i got it. In later case
when it nums[i] is 3 count is incremented by 1.
Now you are checking if prev_value ==3 if yes put count as some dumy 9 value and breaking away from loop so that below tests also pass
{3,1,3,2,3,3}

other wise checking prev_value!=3 after num[i] with && is not 100 % case

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in first approach if array is  like {3.1.3.2.3.3} it is giving true even though it is false as it checks bothe below conditions ahead of time


   

 if(nums[i]==3&&prev_value!=3){

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above is not incrementing count from 3 to 4 wrongly as prev_value!=3 false

moral lesson is breaking to small if cases is better than writing big chunk of if with bunch of && in between i guess

public class HaveThree {

	public static void main(String[] args) {
		int[] ar={3,1,3,3};
    // TODO Auto-generated method stub
    System.out.println("is-->"+haveThree(ar));
	}

	public static boolean haveThree(int[] nums) {
		int cnt = 0;
		if (nums[0] == 3) {
			cnt++;
		}
		for (int i = 1; i < nums.length; i++) {
			if (nums[i] == 3) {
				cnt++;
			}
			if (nums[i] == 3 && nums[i - 1] == 3) {
				return false;
			}
		}
		return cnt == 3;

	}
}

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above gave false while debugging

Just want to point out that gudii9 has been asking these type of questions practically forever. There is no way these are academic assignments (I'll refrain on stating why I believe that). I have frequently tried to offer logical suggestions for his approaches before including any exact code. I thoroughly understand that we are not to provide precise answers for academic assignments and strive to obey that rule. However, I think a review of his many asked questions would demonstrate that this is not a typical academic or self-studying individual.

Hi thermoduric,

The code that I posted in this question a couple of days ago contained 3 comments (in the actual code) which were intended to help the asker to understand how it worked in the areas which I thought explanation may be needed.  I also started my 1st post with a note about a possible improvement to the asker's code (i.e. moving a test out of the loop).

You deleted my 2 posts, providing this as the reason for doing so:

And now your ruling has changed to:

Can you spot any major differences in your requirements above, thermoduric?  Can you see why I'm finding it hard to follow this moving target of what you deem acceptable for self study questions and what you don't?  Please explain.

Personally, I find that sometimes I'll learn better from (understandable) sample code than from teaching myself to do it some long and unnecessarily complex way.  I could have spent days trying to help the asker to see how to do it in an efficient way, but without posting some code (e.g. the 1 liner way of returning the result), the asker may never have got there.

On the basis of the last sentence of yours that I quoted above, would you be able to reinstate my posts, please?

Thanks.
tel2

Hi thermoduric,

I'm sorry for mixing you up with phoffric, who deleted my posts.

Questions:
Q1. Do you have access to the posts of mine that phoffric deleted?  (If not, I can repost them here now, if needed.)
Q2. How do they violate this requrement from you?:

Thanks.
tel2

Hi thermoduric,

> "There was no real attempt at explaining the code you posted, what it does, how it works nor what the asker could expect to learn from it."

I know I've touched on this before, but maybe you missed it so I'll go into more detail here:
Just looking at my 1st post (which was deleted), my real attempt at explaining things was to:
a) Suggest a possible improvement to the asker's code (i.e. moving a test out of the loop).
b) Include 3 comments (in the actual code) which were intended to help the asker to understand how it worked in the areas which I thought explanation may be needed.

Not wanting to spend unnecessary time on going into detail which may not be required, I left it to the asker to ask questions if it was still unclear.  He asked a question (post #41747254), and within an hour seemed to retract it with "i got it now" (post #41747370).

What was lacking on my part?

tel2

Thanks thermoduric for leaving me in confusion about what level of commenting (i.e. explaining/documenting) is acceptable for the future, because if commenting the key areas of my code which I believe may need explanation, is not good enough, then I don't know what is, even with the (conflicting) guidelines that you and phoffric have provided.  If I had explained my code much more than I did (especially without request) then I could be making it too easy for the asker, which could also be argued as being not a good way to aid the process of learning.

In future maybe I need to contact you or phoffric before I post my code, to see if I've commented it to your satisfaction, so it doesn't get deleted.

tel2