Polyfill of reduce, map

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Polyfill of reduce, map are functions that mimic the behavior of the original functions in older browsers.

Polyfill of reduce function can be implemented using a for loop to iterate over the array and accumulate the result.
Polyfill of map function can be implemented using a for loop to iterate over the array and create a new array with the transformed values.
These polyfills are useful for ensuring cross-browser compatibility.
Example of polyfill for reduce function: Array.prototype.reduce = function(callback, initialValue) { var accumulator = initialValue || this[0]; for (var i = initialValue ? 0 : 1; i < this.length; i++) { accumulator = callback(accumulator, this[i], i, this); } return accumulator; }
Example of polyfill for map function: Array.prototype.map = function(callback) { var newArray = []; for (var i = 0; i < this.length; i++) { newArray.push(callback(this[i], i, this)); } return newArray; }

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