Please explain this code: #include # define SIZE 30 using namespace std; int main() {  int stud_test[SIZE];  int index_stud;  int r1=0,r2=0,r3=0,r4=0,r5=0,r6=0,r7=0,r8=0;    cout<<"Please enter the number of students: ";  cin>>index_stud;    //input  for(int i=0;i

Please explain this code:

#include<iostream>

# define SIZE 30

using namespace std;

int main()

{

 int stud_test[SIZE];

 int index_stud;

 int r1=0,r2=0,r3=0,r4=0,r5=0,r6=0,r7=0,r8=0;

 cout<<"Please enter the number of students: ";

 cin>>index_stud;

 //input

 for(int i=0;i<index_stud;i++)

 {

  cout<<"Enter the marks: ";

  cin>>stud_test[i];

 }

 for(int i=0;i<index_stud;i++)

 {

  if((stud_test[i]>=0) && (stud_test[i]<=24) )

  r1=r1+1;

  else if((stud_test[i]>=25) && (stud_test[i]<=49))

  r2=r2+1;

  else if((stud_test[i]>=50) && (stud_test[i]<=74))

  r3=r3+1;

  else if((stud_test[i]>=75) && (stud_test[i]<=99))

  r4=r4+1;

  else if((stud_test[i]>=100) && (stud_test[i]<=124))

  r5=r5+1;

  else if((stud_test[i]>=125) && (stud_test[i]<=149))

  r6=r6+1;

  else if((stud_test[i]>=150) && (stud_test[i]<=174))

  r7=r7+1;

  else if ((stud_test[i]>=175) && (stud_test[i]<=200))

  r8=r8+1;

 }

 cout<<"Number of students which lie in 00-24: "<<r1<<endl;

 cout<<"Number of students which lie in 25-49: "<<r2<<endl;

 cout<<"Number of students which lie in 50-74: "<<r3<<endl;

 cout<<"Number of students which lie in 75-99: "<<r4<<endl;

 cout<<"Number of students which lie in 100-124: "<<r5<<endl;

 cout<<"Number of students which lie in 125-149: "<<r6<<endl;

 cout<<"Number of students which lie in 150-174: "<<r7<<endl;

 cout<<"Number of students which lie in 175-200: "<<r8<<endl;

}