Increment Decrement Js practice Problem

//Practice one
var a = 5
a--
a = a++ - --a
var b = a-- + a
b ++
--b
var c = b ** 2
c--
--c
++c
++b
console.log(a);
console.log(b);
console.log(c);


//Practice two
var a = 5
a = a++
var b = a++
console.log(a);
var c = b++
console.log(b);
console.log(c);


//Practice Three
var a = 5
a = a++
var b = a++
var c = b++
var d = b
console.log(a);
console.log(b);
console.log(c);
console.log(d);