Leetcode : Remove Duplicates from Sorted Array

Question

Why this code is not accepted by Leetcode compiler? My program is running in netbeans. but leetcode compiler is not accepting it.

Here is my code:

import  java.util.Arrays;


public class RemoveDuplicateFromArray {

public static int[] removeDuplicates(int[] nums) {

    int temp, count = 0 ,l = 0;
    temp = nums[0];

  for(int i = 1; i < nums.length - (1 + l); i++ ) {

      if(temp == nums[i]) {
          count = count + 1;

          for(int j = i; j < nums.length - count; j++){
              nums[j] = nums[j+1];
            }

          i = i - 1;

      } else {
          temp = nums[i];
          i = i ;

      }
       l = count;
  }

      nums = Arrays.copyOfRange(nums, 0, nums.length-count);

      if(nums.length == 2){
      if(nums[0] == nums[1]){
          nums = Arrays.copyOfRange(nums, 0, nums.length-1);
      }
  } 

    return  nums;
}

Here is my main mathod:

public static void main(String[] args) {

    int[] nums = new int[] {1,1,1}; // showing error here.
    System.err.println("nums lenght: " +nums.length);

    int new_nums[] = removeDuplicates(nums);

   for(int i : new_nums) {
        System.err.print(i + " ");
}

}

}

The error is :

incompatible types: int[] cannot be converted to int.

what version of Java does this Leetcode tool use? – m.antkowicz Aug 09 '18 at 20:11 — m.antkowicz, Aug 09 '18 at 20:11

Michael Powers · Answer 1 · 2018-08-10T18:49:14.067

3

I expect leetcode is having trouble with this line:

int new_nums[] = removeDuplicates(nums);

This isn't the typical way to define an integer array (this is the C style). Java does support the syntax, but it's a little arcane. See this answer for more detail.

Try this instead:

int[] new_nums = removeDuplicates(nums);

Just tried this on LeetCode, seems to work:

edited Aug 10 '18 at 18:49

answered Aug 09 '18 at 20:25

Michael Powers

1,970
1
7
12

Tried the code you provided on LeetCode, everything seems ok. Can you provide more information about the error you're getting? – Michael Powers Aug 10 '18 at 18:49

score 0 · Answer 2 · answered Aug 12 '18 at 18:10

I would do it a bit like this myself:

import java.util.ArrayList;
import java.util.List;

public class Main {
    public static void main(String[] args) {

        int[] nums = new int[]{1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 5, 6, 7, 7, 7, 8, 9, 0, 0, 0, 0}; 
        System.out.println("nums lenght: " + nums.length);

        int[] new_nums = removeDuplicates(nums);

        for (int i : new_nums) {
            System.out.print(i + " ");
        }

    }
    public static int[] removeDuplicates(int[] nums) {
        List<Integer> found = new ArrayList();
        for (int i = 1; i < nums.length; i++) {
            if (!found.contains(nums[i])) {
                found.add(nums[i]);
            }
        }
        int[] ret = new int[found.size()];
        for(int i = 0; i < found.size(); i++){
            ret[i] = found.get(i);
        }
        return ret;
    }
}

score 0 · Answer 3 · answered Mar 21 '22 at 14:47

public class Solution {
    public int removeDuplicates(int[] nums) {
        int n = nums.length;
        int i = 0;
        int j = 1;
        if (n <= 1) {
            return n;
        }
        while (j <= n - 1) {
            if (nums[i] != nums[j]) {
                nums[i + 1] = nums[j];
                i++;
            }
            j++;
        }
        return i + 1;
    }
}

import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.MatcherAssert.assertThat;

import java.util.Arrays;
import org.junit.jupiter.api.Test;

class SolutionTest {
    @Test
    void removeDuplicates() {
        int[] array = new int[] {1, 1, 2};
        int end = new Solution().removeDuplicates(array);
        assertThat(Arrays.toString(Arrays.copyOfRange(array, 0, end)), equalTo("[1, 2]"));
    }
}

Leetcode : Remove Duplicates from Sorted Array

3 Answers3