Find the storage address of the elements in the two-dimensional array

Array a[m][n] Store in main order in line order

Known two-dimensional array a[m][n] Store in main order in line order , Each element accounts for L Characters , The first address is a[x][y] The address is Loc1, Elements a[i][j] The address for :

Loc(a[i][j]) = Loc1 + [n*(i-x)+(j-y)]*L

Array a[m][n] Store in the main order according to the column order

Known two-dimensional array a[m][n] Store in the main order according to the column order , Each element accounts for L Characters , The first address is a[x][y] The address is Loc2, Elements a[i][j] The address for :

Loc(a[i][j]) = Loc2 + [m*(j-y)+(i-x)]*L

Example

（1） Known two-dimensional array a[5][4] Store in main order in line order , Each element accounts for 6 Characters , The first address is a[1][1] The address is 120, Elements a[4][2] The address for :

Loc(a[4][2]) = 120 + [4*(4-1)+(2-1)]*6 = 198

（2） Known two-dimensional array a[10][20] Store in the main order according to the column order , Each element accounts for 1 Characters , The first address is a[0][0] The address is 120, Elements a[6][12] The address for :

Loc(a[6][12]) = 120 + [10*12+6]*1 = 246