**MASTER OF COMPUTER APPLICATIONS**

Course Code : MCS-012

Course Title : Computer Organisation and Assembly Language Programming

Assignment Number : MCA(I)/012/Assignment/15-16

Maximum Marks : 100

Weightage : 25%

**Perform the following arithmetic operations using binary signed 2’s complement notation for integers. **

You may assume that the maximum size of integers is of **8 bits **including the sign bit. (Please note that the numbers given here are in decimal notation)

i) Add – 128 and 120

ii) Subtract 124 from –99

iii) Add 64 and 61

Please indicate the overflow if it is occurs. Also write how you have identified the overflow.

**i) Add –128 and 120**

First, we have to represent the number in binary notation

The sign of a binary number is represented by *0 as plus* and *1 as minus*

Sign bit 7 -bits

0 / 1 |

Now, Binary value of the given number

128 – 10000000

120 – 01111000

This number value is of more than 8-bits (i.e.**8-bits**) in signed 2’s complement notation also the value remains the same. Hence this number cannot fit inside it.

To add this numbers we will need one more bit, hence **Addition not possible.**