Of course, it's not very interesting that our timer
outputs the same thing every time. Let's complicate
our task and make it so that every second the numbers
are displayed in the console in ascending order:
first 1
, then 2
, then 3
and so on.
To do this, we need a counter variable that will store its values between function runs. It's easy to see that you can just make a global variable:
let i = 0; // the global variable
setInterval(function() {
i++;
console.log(i);
}, 1000);
Let's rewrite it more compactly:
let i = 0;
setInterval(function() {
console.log(++i);
}, 1000);
Or even more compactly using an arrow function:
let i = 0;
setInterval(() => console.log(++i), 1000);
Let a variable be given that initially stores the
number 100
. Start a timer that every second
will decrease the value of this variable by 1
and print this value to the console.