1’s complement is a method of representing signed numbers in binary format. In this method, the bits of the number are inverted, and a 1 is added to the end.

For example, the number 10010 in binary is represented as 01101 in 1’s complement format. The bits are inverted, and a 1 is added to the end. This gives a value of 10100, which is equal to -20 in decimal.

The 1’s complement technique is simple to implement and efficient in terms of space. However, it has some disadvantages. One disadvantage is that it cannot represent the number 0.

Another disadvantage of 1’s complement is that it can be difficult to perform arithmetic operations on signed numbers. For example, addition and subtraction of signed numbers can be error prone.

Despite its disadvantages, 1’s complement is a simple and effective method of representing signed numbers in binary format. It is often used in low-level programming languages, such as C.

Here is an example of how to represent a signed number in 1’s complement format in C:

```
int number = 10010;
// Get the 1's complement of the number.
int complement = ~number;
// Add 1 to the 1's complement.
int one_s_complement = complement + 1;
```

The `number`

variable is a 8-bit integer. The `complement`

variable will store the 1’s complement of the number, and the `one_s_complement`

variable will store the 1’s complement plus 1.

The `~`

operator is used to invert the bits of the `number`

variable. The `+`

operator is used to add 1 to the `complement`

variable.

The 1’s complement of the number can then be used to perform arithmetic operations on the number.