How to remove zeros from int array?

Question

This is my array: int[] test= new int[] {1,0,1,0,0,0,0,0,0,0}

Now I need to remove all the zeros from this array so it will display like this: Output : {1,1}

I tried this code from this link-StackOverFlow but didn't work for me.

    int j = 0;
    for (int i = 0; i < test.length; i++) {
        if (test[i] != 0)
            test[j++] = test[i];
    }
    int[] newArray = new int[j];
    System.arraycopy(test, 0, newArray, 0, j);
    return newArray;

Please help me to solve this.

I've just tried you code and it works fine! newArray = {1,1} — grig, Dec 24 '14 at 14:34
this code is correct, so, please add the complete code of this method and how you pass arguments to it. — Muhammed Refaat, Dec 24 '14 at 14:40

score 3 · Answer 1 · answered Dec 24 '14 at 14:25

3

Use a List instead. Then you can just do list.removeAll(Collections.singleton(0));. Arrays are far harder to use for this kind of thing.

Example:

List<Integer> list = new ArrayList<Integer>(Arrays.asList(1, 0, 2, 0, 3, 0, 0, 4));
list.removeAll(Collections.singleton(0));
System.out.println(list);

Output: [1, 2, 3, 4]

answered Dec 24 '14 at 14:25

Paul Boddington

37,127
10
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Hi thanks for your time, this code didn't work it shows **cannot invoke removeAll(seton array type of int[])** :( – Sri Dec 24 '14 at 14:31
1

No, it won't work on an array. You need to use `List` instead of `int[]`. It's just my advice. Wait a few minutes and somebody will post an answer using `int[]`, but I wouldn't recommend doing it that way. – Paul Boddington Dec 24 '14 at 14:32
yeah got but i need to add that integers dynamically so i used int[], while running program i used like this to add int into array `test = new int[] { Count1, Count2, Count3,` – Sri Dec 24 '14 at 14:38

arbi mahdi · Accepted Answer · 2014-12-24T15:16:41.423

if you insist to work with array you can use this :

int n = 0;
for (int i = 0; i < test.length; i++) {
    if (test[i] != 0)
        n++;
}

int[] newArray = new int[n];
int j=0;

for (int i = 0; i < test.length; i++) {
    if (test[i] != 0)
       { 
         newArray[j]=test[i]; 
         j++;
       }
}

return newArray;

Or Try to use list :

List<Integer> list_result = new ArrayList<Integer>();
for( int i=0;  i<test.length;  i++ )
{
    if (test[i] != 0)
        list_result.add(test[i]);
}
return list_result;

to parse list :

for( int i=0;  i<list_result.size();  i++ )
{
        system.out.pintln((Integer)list_result.get(i));
}

score 0 · Answer 3 · answered Aug 08 '17 at 04:47

0

I'm not familiar with Java, but if there is a Underscore or Lo-dash library you can use; then you can employ .filter functionality;

This code is from Swift;

var numbers = [1,0,1,0,0,0,0,0,0,0]
numbers = numbers.filter({ $0 != 0 })  // returns [1,1]

answered Aug 08 '17 at 04:47

zardon

1,601
4
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How to remove zeros from int array?

3 Answers3