final-value-of-variable-after-performing-operations.py

# Time:  O(n)
# Space: O(1)

class Solution(object):
    def finalValueAfterOperations(self, operations):
        """
        :type operations: List[str]
        :rtype: int
        """
        return sum(1 if '+' == op[1] else -1 for op in operations)