<prompt> Kuandika JavaScript kwamba mahesabu prefix sum array. Kisha kazi ambayo anarudi jumla kutoka l kwa r.  <response>: Heres an example of JavaScript code that calculates a prefix sum array:function prefixSumArrayarr let prefixSums 0; for let i 0; i arr.length; i prefixSumsi1 prefixSumsi arri; return prefixSums;And heres a function that uses the prefix sum array to return the sum of a subarray between two indices l and r:function sumSubarrayl, r, prefixSums return prefixSumsr1 - prefixSumsl;To use these functions:let arr 1, 2, 3, 4, 5;let prefixSums prefixSumArrayarr;console.logsumSubarray1, 3, prefixSums; Output: 9This will calculate the prefix sum array of the original array 1, 2, 3, 4, 5, then return the sum of the subarray between indices 1 and 3, which is 2, 3, 4, and should be equal to 9. 