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Abhishek Chaudhary

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# Final Value of Variable After Performing Operations

There is a programming language with only four operations and one variable `X`:

• `++X` and `X++` increments the value of the variable `X` by `1`.
• `--X` and `X--` decrements the value of the variable `X` by `1`.

Initially, the value of `X` is `0`.

Given an array of strings `operations` containing a list of operations, return the final value of `X` after performing all the operations.

Example 1:

Input: operations = ["--X","X++","X++"]
Output: 1
Explanation: The operations are performed as follows:
Initially, X = 0.
--X: X is decremented by 1, X = 0 - 1 = -1.
X++: X is incremented by 1, X = -1 + 1 = 0.
X++: X is incremented by 1, X = 0 + 1 = 1.

Example 2:

Input: operations = ["++X","++X","X++"]
Output: 3
Explanation: The operations are performed as follows:
Initially, X = 0.
++X: X is incremented by 1, X = 0 + 1 = 1.
++X: X is incremented by 1, X = 1 + 1 = 2.
X++: X is incremented by 1, X = 2 + 1 = 3.

Example 3:

Input: operations = ["X++","++X","--X","X--"]
Output: 0
Explanation: The operations are performed as follows:
Initially, X = 0.
X++: X is incremented by 1, X = 0 + 1 = 1.
++X: X is incremented by 1, X = 1 + 1 = 2.
--X: X is decremented by 1, X = 2 - 1 = 1.
X--: X is decremented by 1, X = 1 - 1 = 0.

Constraints:

• `1 <= operations.length <= 100`
• `operations[i]` will be either `"++X"`, `"X++"`, `"--X"`, or `"X--"`.

SOLUTION:

``````class Solution:
def finalValueAfterOperations(self, operations: List[str]) -> int:
x = 0
for o in operations:
if o[1] == '+':
x += 1
if o[1] == '-':
x -= 1
return x
``````