Requesting explanation of the following c program. The output is 36 and 63, but how?

Question

int a=10, b=25;
a = b++ + a++;
b = ++b + ++a;
printf("%d %d",a,b);
}

Answer 1

at 1st,
a= b++ + ++a (here b=25,a=10 after sum a=35)
b = ++b + ++a( here b=27 ,a=36, after sum b= 63)
so, when print the value then a=36, b=63

Answer 2

int a=10, b=25;
//note: a++ is used, increment is after the variable
a = b++ + a++; //result for a is 35
//b and a here are secretly/already incremented to (b=26, a=11)but cannot reflect value directly to a, the new values of b&&a can only be used on next variable
//note: ++a is used, increment before the variable
b = ++b + ++a; //first, we can now use the new value of (b) which is 26 then incremented again to (b=27) by ++b but, unlike to the first statement, here, it directly used the new value. Second, the new value of (a) was 35 but incremented by ++a then, the newest value is (a=36).
printf("%d %d",a,b);//so, a=36 and b = 36+27;
:hope it helps, im looking for friends, im a 2nd yr student bscpe

Answer 3

This is *COMPLETELY* compiler dependant as modifying a variable more than once in the same statement is undefined behavior