Final Value of Variable After Performing Operations

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

++X and X++ increment 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.

Input Format

First Parameter - number n

Second Parameter - Array arr of strings

Output Format

Return the number

Example 1:

Input:
    3
    --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:
    3
    ++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

Constraints:

• 1 <= arr.length <= 100
• arr[i] will be either ++X, X++, --X, or X--.
• Expected Time Complexity: O(n)
• Expected Space Complexity: O(1)