/*
C | JS
-----------------|------------------
int x; | var x;
-----------------|------------------
int xs[n]; | var xs = [];
-----------------|------------------
printf(...) | console.log(...)
-----------------|------------------
int f (int x) { | function f (x) {
... | ...
return y; | return y;
} | }
The remaining syntax from your post is almost identical in C and JS.
Press F12 in your browser (Chrome or Firefox) and have some fun with JavaScript in the "Console" tab, it's a good starting point :-) For example, copy paste the below code into the browser console and press ENTER.
*/
function add (a, b) {
return a + b;
}
console.log("1 + 1 =", add(1, 1));
add(1, 2);