Can any one explain this?

Question

Its a challenge in java i really cant understand!
public class Program
{
public static void main(String[] args) {
int a=1;int f=5;
for (; (a+=f+1)<7;)
{
f=a% (f+1);
}
System.out.print (f*a);
}
}

output: 35 but but.. how??

Answer 1

there is no initialization & there is no something todo after finishing loop. there is only condition
so FOR was written like that
for(; condition. ;)
condition: a=a+f+1=1+5+1=7
so a<7 is false.. so skip for loop, it won't be executed
finally print f*a=5*7=35

Answer 2

Thank you! ;) @Dina