Time Complexity Of Nested Loops

What is the time complexity of the following code segment? Assume arr is a 2D array with n rows and m columns.

public class NestedLoop {
    public static void main(String[] args) {
        int[][] arr = new int[n][m]; // Array has n rows and m columns

        for (int i = 0; i < arr.length; i++) {
            for (int j = 0; j < arr[0].length; j++) {
                for (int k = 0; k < j; k++) {
                    // Constant-time operation
                    int temp = arr[i][j] + k;
                }
            }
        }
    }
}