How to write a remove method?

Question

Write a method called get which will return an element from the given index. Returns -1 if the index is out-of-bounds.

Write a method called remove which will remove an element from the given index. Returns -1 if the index is out-of-bounds. Data should be shifted accordingly during removal.

//This is the get method 

public int get(int index){

    if(index < 0 || index >= size) {
       return -1;

 }else {
        return data[index];
    }

}

//This is the remove method

public int remove(int index){

    if(index < 0 || index >= size){
        return -1;

    }else {

        for(int i = 0; i < size-1; i++) {
            index[i] = index[i+1];
        }
    }

}

This is as far as I got. Not sure how to proceed with the code. I'd appreciate if someone could guide me through. Thank you!

You need to post the code of the data structure that you are manipulating. — Mohammed Aouf Zouag, Feb 16 '16 at 22:37
`index[i]`?? isn't `index` an integer parameter of your method and not an array? — Atri, Feb 16 '16 at 22:38

tmaxxcar · Accepted Answer · 2016-02-16T22:55:54.440

So far, you have the right idea. I am going to assume based on your syntax, that you are using an array. Your get() method looks good, but you are missing some code from your remove() method.

public int remove(int index){
  //check for out-of-bounds
  if(index < 0 || index >= size) //assumes size is set to the size of the array
  {
    return -1; }
  else
    {
     for(int i = index; i < size-1; i++){
         data[i] = data[i+1]; }
         data[size-1] = 0;  //assuming the array contains numbers, if not replace '0' with null
    }
}

Atri · Answer 2 · 2016-02-16T22:45:45.593

0

You need to replace the following :

    for(int i = 0; i < size-1; i++) {
        index[i] = index[i+1];
    }

with:

    for(int i = index; i < size-1; i++) {
        data[i] = data[i+1];
    }

Start the loop with index
index[i] won't compile. Should be data[i] probably.

Note:
This will not delete the last element. You need to specifically check for it.

edited Feb 16 '16 at 22:45

answered Feb 16 '16 at 22:41

Atri

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In addition, the last element should be set null to avoid a memory leak. – dzidzitop Feb 16 '16 at 22:43

score -2 · Answer 3 · edited Feb 05 '21 at 23:59

public class MyList<T> {

T[] items = (T[])new Object[10];

public int size() {
            
            int counter=0;
            for (int i = 0; i < items.length; i ++) {
                   
                if (items[i] != null) {
                     counter ++;
                }
                   
            }
            return counter;
          }

    public void remove(int t) {
            for (int i = t; i < items.length-1; i++) {
                
                items[i]=items[i+1];        
            }
            
            items[items.length-1]=null;
            
            items= Arrays.copyOf(items,size());     
                        
        }
}

How to write a remove method?

3 Answers3