Sum using reduce

Sum those numbers

const numbers = [5, 10, 15, 20];
const sum = numbers.reduce((acc, value) => acc += value, 0);

Summary

• .reduce() is one of the most versatile array methods in JavaScript. It iterates over every element and accumulates a single result based on the callback function you provide.
• The callback receives an accumulator (acc) and the current value. The accumulator carries the running total, and 0 is the initial value passed as the second argument to .reduce().
• Beyond summing numbers, .reduce() can be used to calculate averages, flatten arrays, group data, and build entirely new data structures.
• It also works with strings and objects, making it a powerful tool for transforming arrays into any shape you need.