## Binary Division by Repeated Subtraction

• Set quotient to zero
• Repeat while dividend is greater than or equal to divisor
• Subtract divisor from dividend
• End of repeat block
• quotient is correct, dividend is remainder
• STOP

## Binary Division by Shift and Subtract

Basically the reverse of the mutliply by shift and add.

• Set quotient to 0
• Align leftmost digits in dividend and divisor
• Repeat
• If that portion of the dividend above the divisor is greater than or equal to the divisor
• Then subtract divisor from that portion of the dividend and
• Concatentate 1 to the right hand end of the quotient
• Else concatentate 0 to the right hand end of the quotient
• Shift the divisor one place right
• Until dividend is less than the divisor
• quotient is correct, dividend is remainder
• STOP

## Binary Multiply - Repeated Shift and Add

Repeated shift and add - starting with a result of 0, shift the second multiplicand to correspond with each 1 in the first multiplicand and add to the result. Shifting each position left is equivalent to multiplying by 2, just as in decimal representation a shift left is equivalent to multiplying by 10.

 Set result to 0 Repeat Shift 2nd multiplicand left until rightmost digit is lined up with leftmost 1 in first multiplicand Add 2nd multiplicand in that position to result Remove that 1 from 1st multiplicand Until 1st multiplicand is zero Result is correct STOP Home