while loop

Question

Why does the output for this is 6 instead of 4??

var x = 3;
var a = 0;
while (a < 3) {
x += 1;
a += 1;
}
println(x);

Answer 1

execution will be like this:
pass1: a=0 0<3 true x=3+1= 4 a=0+1=1
pass2: a=1 1<3 true x=4+1= 5 a=1+1=2
pass3: a=2 2<3 true x=5+1=6 a=2+1=3
pass4: a=3 3<3 false
output: x=6

Answer 2

@Ravi Thank you that make so much sense