Udemy JS Algorithms & Data Structures Masterclass- Section 6 Exercise 8 (1st try)

Sliding Window - minSubArrayLen

Write a function called minSubArrayLen which accepts two parameters - an array of positive integers and a positive integer. This function should return the minimal length of a contiguous subarray of which the sum is greater than or equal to the integer passed to the function. If there isn't one, return 0 instead.

My code efficiency: starts with shortest lengths first (then increments length by 1 each loop) so returns first one greater than or equal to integer.

//loop thru array once and check if any element greater than or equal to integer- return 1 //loop thru array starting from each pointer, iterate to length of 2. If any summed to be greater than or equal to integer, return 2 //From each pointer, iterate to length of 3. If any summed to be greater or equal to integer, return 3. //... function minSubArrayLen(arr, num) { let pointer = 0; let currLength = 1; for (let i = pointer; i < arr.length; i++) { if (arr[i] >= num) return currLength; } currLength++; let startingLength = 2; while (currLength <= arr.length) { //pointer = 1, currLength = 3; let sum = 0; for (let i = pointer; i < currLength; i++) { sum += arr[i]; } if (sum >= num) { console.log(sum); return currLength - pointer; } if (pointer === 0 && currLength === arr.length - 1) return 0; pointer++; currLength++; if (currLength > arr.length) { pointer = 0; currLength = startingLength++; } } }

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