MinimumValuetoGetPositiveStepbyStepSum.cpp

// LEETCODE:
// Minimum Value to Get Positive Step by Step Sum
// https://leetcode.com/problems/minimum-value-to-get-positive-step-by-step-sum/description/

// Given an array of integers nums, you start with an initial positive value startValue.
// In each iteration, you calculate the step by step sum of startValue plus elements in nums (from left to right).

// Return the minimum positive value of startValue such that the step by step sum is never less than 1.

// Example 1:

// Input: nums = [-3,2,-3,4,2]
// Output: 5
// Explanation: If you choose startValue = 4, in the third iteration your step by step sum is less than 1.
// step by step sum
// startValue = 4 | startValue = 5 | nums
//   (4 -3 ) = 1  | (5 -3 ) = 2    |  -3
//   (1 +2 ) = 3  | (2 +2 ) = 4    |   2
//   (3 -3 ) = 0  | (4 -3 ) = 1    |  -3
//   (0 +4 ) = 4  | (1 +4 ) = 5    |   4
//   (4 +2 ) = 6  | (5 +2 ) = 7    |   2
// Example 2:

// Input: nums = [1,2]
// Output: 1
// Explanation: Minimum start value should be positive. 
// Example 3:

// Input: nums = [1,-2,-3]
// Output: 5

class Solution {
public:
    int minStartValue(vector<int>& nums) {
        int minSum = INT_MAX, sum = 0;
        for(int i = 0; i < nums.size(); i++){
            sum+=nums[i];
            minSum = min(minSum, sum);
        }
        if(minSum > 0){
            return 1;
        }
        int res = minSum * (-1) + 1;
        if(res < 0){
            return res * -1;
        }
        if(res == 0){
            return 1;
        }
        return res;
    }
};