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JavaScript: Apply a function against an accumulator and each element in the array (from left to right), returning an array of successively reduced values

JavaScript: Exercise-156 with Solution

Write a JavaScript program to apply a function against an accumulator and each element in the array (from left to right), returning an array of successively reduced values.

  • Use Array.prototype.reduce() to apply the given function to the given array, storing each new result.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const reduceSuccessive = (arr, fn, acc) =>
  arr.reduce((res, val, i, arr) => (res.push(fn(res.slice(-1)[0], val, i, arr)), res), [acc]);

console.log(reduceSuccessive([1, 2, 3, 4, 5, 6], (acc, val) => acc + val, 0));

Sample Output:

[0,1,3,6,10,15,21]

Flowchart:

flowchart: Apply a function against an accumulator and each element in the array (from left to right), returning an array of successively reduced values

Live Demo:

See the Pen javascript-basic-exercise-156-1 by w3resource (@w3resource) on CodePen.


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