What does parantheses do in this code

Question

#include<stdio.h>
int main()
{
Int a,x=(2,3,4,5);
a=1,2,3,4,5;
Printf("%d%d",x,a);
return 0;
}

Answer 1

With parentheses, the comma operator is in effect.

https://docs.microsoft.com/en-us/cpp/cpp/comma-operator?view=vs-2019

For expression (a, b), a is evaluated, and then b is evaluated. The value of b is returned for the entire statement.

Without parentheses, the assignment operator takes precedence over the comma operator, assigning 1 to a.