# How to convert a 2D array into 1D array in C#?

Set a two-dimensional array and a one-dimensional array −

int[,] a = new int[2, 2] {{1,2}, {3,4} };
int[] b = new int[4];

To convert 2D to 1D array, set the two dimensional into one-dimensional we declared before −

for (i = 0; i < 2; i++) {
for (j = 0; j < 2; j++) {
b[k++] = a[i, j];
}
}

The following is the complete code to convert a two-dimensional array to one-dimensional array in C# −

## Example

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace Program {
class twodmatrix {

static void Main(string[] args) {
int[, ] a = new int[2, 2] {
{
1,
2
},{
3,
4
}
};

int i, j;
int[] b = new int[4];
int k = 0;

Console.WriteLine("Two-Dimensional Array...");
for (i = 0; i < 2; i++) {

for (j = 0; j < 2; j++) {
Console.WriteLine("a[{0},{1}] = {2}", i, j, a[i, j]);
}
}

Console.WriteLine("One-Dimensional Array...");
for (i = 0; i < 2; i++) {
for (j = 0; j < 2; j++) {
b[k++] = a[i, j];
}
}

for (i = 0; i < 2 * 2; i++) {
Console.WriteLine("{0}\t", b[i]);
}
}