Running Sum of 1d Array

Author: nirmalnishant645

1480-Running-Sum-of-1d-Array.py

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+'''
+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, 1+2, 1+2+3, 1+2+3+4].
+
+Example 2:
+Input: nums = [1,1,1,1,1]
+Output: [1,2,3,4,5]
+Explanation: Running sum is obtained as follows: [1, 1+1, 1+1+1, 1+1+1+1, 1+1+1+1+1].
+
+Example 3:
+Input: nums = [3,1,2,10,1]
+Output: [3,4,6,16,17] 
+
+Constraints:
+1 <= nums.length <= 1000
+-10^6 <= nums[i] <= 10^6
+'''
+
+# Normal Iteration and Addition
+
+class Solution:
+ def runningSum(self, nums: List[int]) -> List[int]:
+ res = [nums[0]]
+ for num in nums[1:]:
+ res.append(res[-1] + num)
+ return res
+
+# Normal Iteration and Addition in the Input Array
+
+class Solution:
+ def runningSum(self, nums: List[int]) -> List[int]:
+ for i, num in enumerate(nums[1:]):
+ nums[i+1] = nums[i]+num
+ return nums
+
+# Normal Iteration and Addition in the Input Array II
+
+class Solution:
+ def runningSum(self, nums: List[int]) -> List[int]:
+ for i in range(1, len(nums)):
+ nums[i] += nums[i-1]
+ return nums