Js closure question: is there a boss who can explain how this code is executed?

this is a common closure problem:

I would like to ask you guys, how is this code executed?
for example, when you click 3, how do you print out 2?

< hr >

1 < / div >
2 < / div >
3 < / div >
4 < / div >
5 < / div >

< script > 

var elem = document.getElementsByTagName("div"); // 5div

for (var i = 0; i < 5; iPP) {
    console.log(i);
    (function (w) {
        elem[w].onclick = function () {
            console.log(w);
        };
    })(i);
}

< / script >

Javascript css html
May.16,2021
The argument to the self-executing function in the

for loop comes from I. When you click on it, the argument I is passed to the parameter w. When you click on the third element, the div content starts at 1

your div content starts at 1, and the index for the loop starts at 0, so the pop-up value will be 1

when you click on the third element. 1-5
I starts with 0, 0-4
so when you click on div3, the third bit is 2, because 0 is the first bit of I, 1 is the second bit of I, and 2 is the third bit of I 

var elem = document.getElementsByTagName('div'); // 5div

for (var i = 0; i < 5; iPP) {
    console.log(i);
    (function (w) {
        elem[w].onclick = function () {    -sharp idiv
            console.log(w);
        };
    })(i);    -sharp 0-4
}

"immediate execution function" retains the value of each "I" and binds each "div" separately,
so when you click "div3", Will output "2"
(starting at 0, so it is 2)

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