We can declare a nested structure as the nested loop. This means we can define a structure inside another structure. The basic syntax of a nested structure is as follows:

struct firstStructure { // our first structure  
  //variables 
}; 
struct secondStructure { // Our second structure 
  struct firstStruct objName; //Created object of fist  structure(Nesting) 
  //More variables 
}; 

Let's look at an example. Let's say we need two types of information about a student, basic information and personal information. The basic information includes the name and roll number. The personal information includes age, phoneNum and sex. The structures of the two types of information will be as follows:

struct basicInfo { // our first structure 
  String name; 
  int roll; 
}; 
struct personalInfo { //our second structure. 
  int age; 
  int phoneNum; 
  char sex; 
}; 

We will nest the first structure to the...