STEP 1 : Find a block that has no predefined number.

STEP 2 : Return a positive boolean result if all blocks are filled.

STEP 3 : Run a loop running ‘$order_of_matrix’ times

STEP 4a: Assign a digit, that is not already assigned in the row or column or the respective sub-domain, to the block.

STEP 4b: If the digit cannot be filled in the block, the subtree is nullified and the possibility is removed.

STEP 4c: Move on to the next iteration.

STEP 4d: This process is repeated till the criteria of “STEP 2” is fulfilled.

STEP 5 : Return a negative boolean result if none of the digits can be placed in a block(which breaks out of the backtracking algorithm).