What is the difference between prefix and postfix operators?

Question

The following code prints a value of 9. Why? Here return(i++) will return a value of 11 and due to --i the value should be 10 itself, can anyone ex

Answer 1

Let's keep this as simple as possible.

let i = 1
console.log('A', i)    // 1
console.log('B', ++i)  // 2
console.log('C', i++)  // 3
console.log('D', i)    // 4

A) Prints the value of i B) First i is incremented then the console.log is run with i as it's new value C) Console.log is run with i at its current value, then i will get incemented D) Prints the value of i

In short if you use the pre-shorthand i.e(++i) i will get updated before the line is executed. If you use the post-shorthand i.e(i++) the current line will run as if i had not been updated yet then i gets increased so ther next time your interpreter comes accross i it will have been increrased.