nested structure in c
The members of a structure can be a of any data type including another structure type. so we can declare or include structure with in another structure.
so in this A structure variable can be a member of another structure.This is called nesting of structures.
.
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tag0
{
member1;
member2;
member3;
…….
tag1
{
member1;
member2;
member3;
…….
}var1;
…..
….
member n;
}var2;
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for accessing member1 of inner structure struct tag2 we write
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Employee
{
name[15];
empid;
date
{
day;
month;
year;
}birthinfo;
salary;
}
emp1,emp2;
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so in this example we have defined a structure date with in Employee structure. The structure date has three members
day,month and year and birthinfo is the variable of type struct date. we can access the members of inner structure as
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emp1.birthinfo.day day of birthinfo of emp1
emp1.birthinfo.month month of birthinfo of emp1
emp1.birthinfo.year year of birthinfo of emp1
emp2.birthinfo.day day of birthinfo of emp2
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so we have defined the template of the structure date inside the strucure Employee, we also can defined it outside and declare its variables inside the structure Employee using the tag.
but always remember if we define the inner structure outside, then this defination should always be before the defination of outer structure. now take the example in this example date structure should be defined before the Employee structure
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date
{
day;
month;
year;
};
Employee
{
name[20];
empid;
salary;
date birthinfo;
}emp1,emp2;
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Employee
{
name[15];
empid;
salary;
date joindate,leavedate;
}emp1,emp2;
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