# LeetCode: Running Sum Of 1d Array Solution

*Accumulate*

## Approach

Either mutate array by accumulate sum or calculate prefix sum

## Implementation

1// approach 1: mutate the array2var runningSum = function (nums) {3 for (let i = 1; i < nums.length; i++) {4 nums[i] += nums[i - 1]5 }6 return nums7}89// approach 2: prefix sum10var runningSum = function (nums) {11 const prefixSums = []12 let sum = 013 for (const num of nums) {14 sum += num15 prefixSums.push(sum)16 }17 return prefixSums18}

## References

## Comments

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## Tags

leetcode

array

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