The array can be initialized in more than one way at the time of 2-D array declaration.
For example
int matrix[4][3] = {
{10,20,30},// Initializes row 0
{40,50,60},// Initializes row 1
{70,80,90},// Initializes row 2
{100,110,120}// Initializes row 3
};
int matrix[4][3] = {10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120};
Array’s row size is optional but column size is compulsory.