C++

Data Types in C++

Data Type: A set of values together with a set of operations.

C++ data types fall into 3 categories:

  1. Simple data type
  2. Structured data type
  3. Pointers

Simple Data Types

They are three types of Simple Data Types

  1. Integral – which is a data type that deals with integers.
  2. Floating-Point – which is a data type that deals with decimal numbers.
  3. Enumeration Type – it is a user-defined data type.

Integral Data type:

  • char
  • short
  • int
  • long
  • bool
  • unsigned char
  • unsigned short
  • unsigned int 
  • unsigned long

Every Data type has a different set of values associated with it.

Data TypeValuesStorage(in bytes)
int-2147483648 to 21474836471
booltrue or false1
char-128 to 1271

Type Modifiers

The range of the data types can be modified by using the type modifiers.

unsigned: target data type will be represented in the unsigned representation.

signed: target data type will be represented in the signed representation.

short: target data type will have a width of at least 16 bits.

long: target data type will have a width of at least 32 bits.

long long: target data type will have a width of at least 64 bits.

int DATA TYPE

Integers in C++, as in mathematics, are numbers such as 10,-12,45,98574,-765….

Code:

C++ Code

#include<iostream>

using namespace std;
int main() {
  int studentId = 87;
  cout << "StudentId is " << studentId;
  //to store the integer values we use int dataType
  return 0;
}

Output: StudentId is 87

bool DATA TYPE

The boolean data type has only two values: true or false.

Code:

C++ Code

#include<iostream>

using namespace std;
int main() {
  bool isStudentPresent = true;
  if (isStudentPresent) {
    cout << "Student is present";
  } else {
    cout << "Student is absent";
  }
  return 0;
}

Output: Student is present

char DATA TYPE

The data type char is the smallest integral data type. The char data type is used to represent characters.

Characters such as ‘a’, ‘&’, ‘S’, ‘*’

Code:

C++ Code

#include<iostream>

using namespace std;
int main() {
  char sectionNumber = 'C';
  cout << "The Student belongs to Section " << sectionNumber;
  return 0;
}

Output: The Student belongs to Section C

Floating – Point Data type

Floating point data type deals with the decimal numbers.

C++ provides three floating-point data types.

  1. float
  2. double
  3. long double

float: The data type float is used to represent any real number between -3.4E+38 and 3.4E+38.

The memory allocated is 4 bytes.

Code:

C++ Code

#include<iostream>

using namespace std;
int main() {
  float avgPercentage = 92.3;
  cout << "The average Percentage of the student is " << avgPercentage << "%";
  return 0;
}

Output: The average Percentage of the student is 92.3%

double: The data type double is used to represent any real number between -1.7E+308 and 1.7E+308.The memory allocated is 8 bytes.

C++ Program to illustrate the usage of data types

Code:

C++ Code

#include<iostream>

using namespace std;

int main() {

  int student_ID = 102; //to store integers we use int.
  char section_NO = 'A'; // to store characters we use char.
  bool isPresent = true; //to store the boolean values we use bool.

  float examScoreAverage = 92.76; //to store the decimal numbers we use float.
  double distanceToSchool = 12345.76; //double is same as float but with extra bytes of memory to store larger values.

  cout << "The size of int is: " << sizeof(int) << " Bytes" << endl;
  cout << "The size of char is: " << sizeof(char) << " Bytes" << endl;
  cout << "The size of bool is: " << sizeof(bool) << " Bytes" << endl;
  cout << "The size of float is: " << sizeof(float) << " Bytes" << endl;
  cout << "The size of double is: " << sizeof(double) << " Bytes" << endl;
  cout << "The size of long double is: " << sizeof(long double) << " Bytes" << endl;

}

Output:

The size of int is: 4 Bytes
The size of char is: 1 Bytes
The size of bool is: 1 Bytes
The size of float is: 4 Bytes
The size of double is: 8 Bytes
The size of long double is: 16 Bytes