twister_void twister_void - 1 month ago 4
Java Question

Union of 2 arrays in java?

My code

class Union {

//Search Function
static boolean search(int A[], int i) {

for (int k = 0; k < A.length; k++) {
if (A[k] == i) {
return true;
}
}
return false;
}

//union
static void union(int A[][], int B[][]) {

int i = 0;
int count = 0;
int C[] = new int[A.length + B.length];

for (; i < A.length; i++) {
if (!(search(B, A[i]))) {
C[count] = A[i];
count++;
}
}

for (; i < (A.length + B.length); i++) {
C[count] = B[i - A.length];
count++;
}

System.out.println("This is Union Of 2 D Array ");
System.out.println();

for (int k = 0; k < count; k++) {
System.out.println(C[k]);
}
System.out.println();

}

public static void main(String... s) {
union(new int[]{1, 1, 1, 4,}, new int[]{1, 4, 4, 4, 1, 2});
}
}


I am using this output to find union of 2d array .but output which i am getting is wrong . i don't want 2 use any predefined interface and method in java .
my answer should be
{1,2,4}

Example

A= {1,2,3,3}
B={2,3,1,1}
c={1,2,3}

Answer

This is what you are looking for:

import java.util.Arrays;

public class Union
{

    public static void main(String[] args)
    {
        int[] A = {1, 2, 3, 3};
        int[] B = {2, 3, 1, 1};
        System.out.println(Arrays.toString(unionArrays(A, B)));
    }

    /* Union of multiple arrays */
    public static int[] unionArrays(int[]... arrays)
    {
        int maxSize = 0;
        int counter = 0;

        for(int[] array : arrays) maxSize += array.length;
        int[] accumulator = new int[maxSize];

        for(int[] array : arrays)
            for(int i : array)
                if(!isDuplicated(accumulator, counter, i))
                    accumulator[counter++] = i;

        int[] result = new int[counter];
        for(int i = 0; i < counter; i++) result[i] = accumulator[i];

        return result;
    }

    public static boolean isDuplicated(int[] array, int counter, int value)
    {
        for(int i = 0; i < counter; i++) if(array[i] == value) return true;
        return false;
    }
}

OUTPUT:

[1, 2, 3]