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JavaScript: Return the minimum-maximum value of an array, after applying the provided function to set comparing rule

JavaScript fundamental (ES6 Syntax): Exercise-15 with Solution

Write a JavaScript program to return the minimum-maximum value of an array, after applying the provided function to set comparing rule.

  • Use Array.prototype.reduce() in combination with the comparator function to get the appropriate element in the array.
  • Omit the second argument, comparator, to use the default one that returns the minimum element in the array.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const reduce_Which = (arr, comparator = (a, b) => a - b) =>
  arr.reduce((a, b) => (comparator(a, b) >= 0 ? b : a));
console.log(reduce_Which([1, 3, 2])); 
console.log(reduce_Which([10, 30, 20], (a, b) => b - a));  
console.log(reduce_Which(
  [{ name: 'Kevin', age: 16 }, { name: 'John', age: 20 }, { name: 'Ani', age: 19 }],
  (a, b) => a.age - b.age)); 

Sample Output:

1
30
{"name":"Kevin","age":16}

Flowchart:

flowchart: Return the minimum-maximum value of an array, after applying the provided function to set comparing rule

Live Demo:

See the Pen javascript-basic-exercise-1-15 by w3resource (@w3resource) on CodePen.


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JavaScript: Tips of the Day

Returns an array of n-tuples of consecutive elements

Example:

const tips_arr = (n, arr) =>  n > arr.length ? [] : arr.slice(n - 1).map((v, i) =>[...arr.slice(i, i + n - 1), v]);
console.log(tips_arr(2, [1, 2, 3, 4, 5])); 
console.log(tips_arr(3, [1, 2, 3, 4, 5]));
console.log(tips_arr(5, [1, 2, 3, 4]));

Output:

[[1, 2], [2, 3], [3, 4], [4, 5]]
[[1, 2, 3], [2, 3, 4], [3, 4, 5]]
[]