Chapter 11 structs C records 11 1 In CS 1A we worked with a database program We viewed the data in the database as being stored in records Each record was a collection of fields A record then was a complete set of information about a person place or object and the fields defined the individual components of the record C refers to records as structs We defined an array as a collection of information all of the same type homogeneous A struct then is a collection of information of different data types heterogeneous The fields of a struct are referred to as members struct StructName dataType memberName Example struct StudentRec string name string idNum float gpa StudentRec theStudent theStudent name idNum gpa 11 2 The individual members of the struct must be accessed by the name of the struct followed by the name of the member theStudent name Sally cin theStudent idNum cout theStudent gpa Example This program demonstrates the use of a record C struct include iostream h struct PersonRec string lastName string firstName int age void main void PersonRec thePerson cout Enter first name cin thePerson firstName cout Enter last name cin thePerson lastName cout Enter age cin thePerson age cout cout n nHello thePerson firstName thePerson lastName How are you n nCongratulations on reaching the age of thePerson age n 11 3 This program demonstrates the use of a nested struct struct GradeRec float percent char grade struct StudentRec string lastName string firstName int age GradeRec courseGrade void main void StudentRec student cout Enter first name cin student firstName cout Enter last name cin student lastName cout Enter age cin student age cout Enter overall percent cin student courseGrade percent if student courseGrade percent 90 student courseGrade grade A else if student courseGrade percent 75 student courseGrade grade B else student courseGrade grade F cout cout cout n nHello student firstName student lastName How are you n nCongratulations on reaching the age of student age n Your overall percent score is student courseGrade percent for a grade of student courseGrade grade OUTPUT Enter Enter Enter Enter first name Sally last name Smart age 19 overall percent 98 Hello Sally Smart How are you Congratulations on reaching the age of 19 Your overall percent score is 98 for a grade of A 11 4 This program demonstrates the use of an array of structs include iostream h struct PersonRec string lastName string firstName int age typedef PersonRec PeopleArrayType 10 an array of 10 structs void main void PeopleArrayType people a variable of the array type for int i 0 i 10 i cout Enter first name cin people i firstName cout Enter last name cin people i lastName cout Enter age cin people i age for int i 0 i 10 i cout people i firstName people i lastName setw 10 people i age 11 5 include iostream h struct PersonRec string lastName string firstName int age typedef PersonRec PeopleArrayType 10 an array of 10 structs void LoadArray PeopleArrayType peop void main void PeopleArrayType people a variable of the array type LoadArray people output the array for int i 0 i 10 i cout people i firstName people i lastName setw 10 people i age void LoadArray PeopleArrayType peop for int i 0 i 10 i cout Enter first name cin peop i firstName cout Enter last name cin peop i lastName cout Enter age cin peop i age 11 6 structs and Aggregate Operations Aggregate I O is not allowed I O must be performed on a member by member basis Aggregate assignment is allowed All data members fields are copied Aggregate arithmetic is not allowed Aggregate comparison is not allowed Comparisons must be performed on a member by member basis structs may be passed by value or by reference A struct is a valid return type for a value returning function 11 7 Name s Due Date Palindrome Lab struct Write a C program to manage a user defined string The program will create a string from the input buffer output the string and its length and check the string to determine whether or not it is a palindrome A palindrome is a string that reads the same forwards and backwards Examples radar racecar a man a plan a canal panama struct StringRec int strLen char theStr 256 void AddChar StringRec str char theCh adds one character to the string void OutputString StringRec str outputs the string and the length of the string bool CheckString StringRec str returns true if string is a palindrome false otherwise void main void StringRec theString char theChar theString strLen 0 cout Enter a string cin get theChar while theChar n AddChar theString theChar cin get theChar OutputString theString if CheckString theString cout n nThe string is a palindrome else cout n nThe string is not a palindrome 11 8