1658. Minimum Operations to Reduce X to Zero

class Solution:
    def minOperations(self, nums: List[int], x: int) -> int:
        # If we can find sequence with sum (totalSum-x) within array, then the rest of array contain sum = x
        # for finding minimum length, we will find longest sequence with sum (totalSum-x)
        
        totalSum = 0
        
        for num in nums:
            totalSum += num
            
        if totalSum == x:
            return len(nums)
        if totalSum < x:
            return -1
        
        prefixSum, total, maxLen, target = {0: -1}, 0, 0, totalSum-x
        
        for i in range(0,len(nums)):
            total += nums[i]
            
            if total-target in prefixSum:
                maxLen = max(maxLen, i - prefixSum[total-target])
            
            
            prefixSum[total] = i
        
        return -1 if maxLen == 0 else len(nums)-maxLen