How does the function returns 11?

Question

Java
https://code.sololearn.com/c3X10t2XQp6w/?ref=app

Answer 1

a=2
b=6
c=2
In loop
c+=c => c=c+c
c=2+2=4
c++ => c=c+1
c=5
In loop
c=c+c
c=5+5=10
c++ => c=c+1
c=10+1=11
c<b false exit from loop
return c //c=11

Answer 2

Vadivelan thank you