**Set.discard(), remove() & pop() Python**

### Problem Statement :

.remove(x) This operation removes element x from the set. If element x does not exist, it raises a KeyError. The .remove(x) operation returns None. Example: >>> s = set([1, 2, 3, 4, 5, 6, 7, 8, 9]) >>> s.remove(5) >>> print s set([1, 2, 3, 4, 6, 7, 8, 9]) >>> print s.remove(4) None >>> print s set([1, 2, 3, 6, 7, 8, 9]) >>> s.remove(0) KeyError: 0 .discard(x) This operation also removes element x from the set. If element x does not exist, it does not raise a KeyError. The .discard(x) operation returns None. Example: >>> s = set([1, 2, 3, 4, 5, 6, 7, 8, 9]) >>> s.discard(5) >>> print s set([1, 2, 3, 4, 6, 7, 8, 9]) >>> print s.discard(4) None >>> print s set([1, 2, 3, 6, 7, 8, 9]) >>> s.discard(0) >>> print s set([1, 2, 3, 6, 7, 8, 9]) .pop() This operation removes and return an arbitrary element from the set. If there are no elements to remove, it raises a KeyError. Example: >>> s = set([1]) >>> print s.pop() 1 >>> print s set([]) >>> print s.pop() KeyError: pop from an empty set Task: You have a non-empty set s, and you have to execute N commands given in N lines. The commands will be pop, remove and discard. Input Format: The first line contains integer N, the number of elements in the set s. The second line contains N space separated elements of set s. All of the elements are non-negative integers, less than or equal to 9. The third line contains integer N, the number of commands. The next N lines contains either pop, remove and/or discard commands followed by their associated value. Constraints: 1. 0<n<20 2. 0<N<20 Output Format: Print the sum of the elements of set s on a single line.

### Solution :

` ````
Solution in C :
n = input()
s = set(map(int, input().split()))
for i in range(int(input())):
c = input().split()
if c[0] == 'pop':
s.pop()
elif c == 'remove':
s.remove(int(c[1]))
else:
s.discard(int(c[1]))
print(sum(s))
```

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