Hello coders, today we are going to solve **Set.difference() Operation HackerRank Solution** in **Python**.

**Objective**

**.difference()**

The tool *.difference()* returns a set with all the elements from the set that are not in an iterable.

Sometimes the `-`

operator is used in place of the *.difference()* tool, but it only operates on the set of elements in *set*.

Set is immutable to the *.difference()* operation (or the `-`

operation).

```
>>> s = set("Hacker")
>>> print s.difference("Rank")
set(['c', 'r', 'e', 'H'])
>>> print s.difference(set(['R', 'a', 'n', 'k']))
set(['c', 'r', 'e', 'H'])
>>> print s.difference(['R', 'a', 'n', 'k'])
set(['c', 'r', 'e', 'H'])
>>> print s.difference(enumerate(['R', 'a', 'n', 'k']))
set(['a', 'c', 'r', 'e', 'H', 'k'])
>>> print s.difference({"Rank":1})
set(['a', 'c', 'e', 'H', 'k', 'r'])
>>> s - set("Rank")
set(['H', 'c', 'r', 'e'])
```

**Task**

Students of District College have a subscription to *English* and *French* newspapers. Some students have subscribed to only the *English* newspaper, some have subscribed to only the *French* newspaper, and some have subscribed to both newspapers.

You are given two sets of student roll numbers. One set has subscribed to the *English* newspaper, and one set has subscribed to the *French* newspaper. Your task is to find the total number of students who have subscribed to *only English* newspapers.

**Input Format**

The first line contains the number of students who have subscribed to the *English* newspaper.

The second line contains the space separated list of student roll numbers who have subscribed to the *English* newspaper.

The third line contains the number of students who have subscribed to the *French* newspaper.

The fourth line contains the space separated list of student roll numbers who have subscribed to the *French* newspaper.

**Constraints**

**0 < Total number of students in colleges < 1000**

**Output Format**

Output the total number of students who are subscribed to the *English* newspaper *only*.

**Sample Input**

```
9
1 2 3 4 5 6 7 8 9
9
10 1 2 3 11 21 55 6 8
```

**Sample Output**

`4`

**Explanation**

The roll numbers of students who *only* have *English* newspaper subscriptions are:**4, 5, 7** and **9**.

Hence, the total is **4** students.

**Solution – Set.difference() Operation in Python **

# Enter your code here. Read input from STDIN. Print output to STDOUT _ = int(input()) SET_N = set(map(int, input().split())) _ = int(input()) SET_B = set(map(int, input().split())) NEW_SET = SET_N.difference(SET_B) print(len(NEW_SET))

**Disclaimer: **The above Problem **(Set.difference() Operation)** is generated by **Hacker Rank** but the Solution is Provided by **CodingBroz**. This tutorial is only for **Educational** and** Learning **Purpose.