Running Sum of 1d Array

Source Link : https://leetcode.com/problems/running-sum-of-1d-array/

Problem Statement: Given an array nums. We define a running sum of an array as runningSum[i] = sum(nums[0]…nums[i]). Return the running sum of nums.

Example 1: Input: nums = [1,2,3,4] Output: [1,3,6,10] Explanation: Running sum is obtained as follows: [1,].

Example 2: Input: nums = [1,1,1,1,1] Output: [1,2,3,4,5] Explanation: Running sum is obtained as follows: [1,].

Example 3: Input: nums = [3,1,2,10,1] Output: [3,4,6,16,17]

Solution 1: Using extra memory

        public int[] RunningSumLess(int[] nums)
        {
            int[] result = new int[nums.Length];
            if (nums.Length < 2)
            {
                return nums;
            }
            result[0] = nums[0];
            for (int i = 1; i < nums.Length; i++)
            {
                result[i] = nums[i] + result[i - 1];
            }
            return result;
        }

Solution 2: Using same array

         public int[] RunningSum(int[] nums)
        {
            if (nums.Length < 2)
            {
                return nums;
            }
            for (int i = 1; i < nums.Length; i++)
            {
                nums[i] = nums[i] + nums[i - 1];
            }
            return nums;
        }