Question

How can I flatten the 2 dimensions array int originalArray[][] to 1 dimension array?

    int a [] = {1,2,6,7,2};
    int b [] = {2,44,55,2};
    int c [] = {2,44,511,33};

    int originalArray [][] = new int[][]{a,b,c};

Answer 1

A simple for loop will do, it is not difficult, but will depend on the order in which you want to copy the values. For instance (based on the fact that in your example the arrays all have the same length):

int[] newArray = new int[3 * a.length];
int index = 0;
for (int n = 0; n < a.length; n++) {
    newArray[index++] = a[n];
    newArray[index++] = b[n];
    newArray[index++] = c[n];
}

or (different order, a, b, c can be of different lengths):

int[] newArray = new int[a.length + b.length + c.length];
System.arraycopy(a, 0, newArray, 0, a.length);
System.arraycopy(b, 0, newArray, a.length, b.length);
System.arraycopy(c, 0, newArray, a.length + b.length, c.length);