Write comment every single line please in following code

#include

int main()
{

unsigned int Id;
printf("Enter 8 digit stud id number\\");
scanf("%d",&Id);
int n;
char set;
int psi,E;
n=Id%10;
unsigned int k=Id;
while(k>99)
k=k/10;
n=n+k%10;
n=n*2;
if(n>14&&n<=19)
{

set=\'A\';
psi=2;
E=4;
}
else if(n>=20&&n<=25)
{

set=\'B\';
psi=3;
E=2;

}
else if(n>=26&&n<=31)
{
set=\'C\';
psi=3;
E=3;

}
else if(n>=33&&n<=36)
{
set=\'D\';
psi=2;
E=3;
}
printf("Student id number=%u\\",Id);
printf("Question set=%c\\",set);
printf("Variable values psi=%d E=%d", psi,E);

return 0;
}