Lab 10

1
Lab 10

• Representation And Conversion of Numeric Types
• Difference between Numeric Types
• Automatic conversion of Data types
• Explicit Conversion of Data Types
• Enumeration
• Note
• Read the whole Chapter 7.

2
Representation And Conversion of Numeric Types

• Type int and double have different internal
  representations. Type int values are represented
  as binary numbers with the leftmost bit
  containing of the sign of the number. While type
  double are represented by a binary exponent and
  mantissa. Real number mantissa2exponent.
• Additional integer types are short, and long.
  Type short represents a smaller range than type
  int. Long represents a larger range than type
  int. (sizeof() can be used to know the size of
  memory block).
• Additional floating point types are float that
  represents a smaller range than type double and
  long double that represents a larger range than
  type double.
• Arithmetic with floating-point data may not be
  precise, because not all real numbers can be
  represented exactly. Other types of numerical
  errors include cancellation error, arithmetic
  overflow error and underflow error.

3

• Type char data are represented by storing a
  binary code value for each symbol. ASCII is a
  commonly used character code.
• A variable or expression can be explicitly
  converted to another type by writing the new
  types name in parentheses before the value to
  convert. Such a cast is very high precedence
  operation. average(double)sum/N given sum and N
  are declared as int and average as double.
• You can declare your own data types in C using
  the reserved work typedef
• Syntax typedef enum identifier_list enum_type
• Example typedef enum Sunday, Monday, Tuesday,
  Wednesday, Thursday, Friday, Saturday day_t
• Defining an enumerated type requires listing the
  identifiers that are the values of the type. Each
  value is represented by an integer. Using the
  enumerated types makes the programs more readable
  because the types values are meaningful for a
  particular application.

4
Enumeration Example

• includeltstdio.hgt
• typedef enumGood, Bad result
• int main()
• result x
• printf("Enter the result ")
• scanf("d",x)
• switch(x)
• case Good
• printf("Good \n")
• break
• case Bad
• printf("Bad \n")
• break
• default printf("Wrong input \n")
• return 0

5
Exercises

• write a program that display the ranges of
  numeric data of type int and long. (Hints use
  limits.h)
• int k5, m4,n
• double x1.5, y2.1,z
• How are zk/m and nxy are evaluated ?
• What is the difference between the following
  statements given frac is of type double and n1
  and d1 are of type int.
• frac n1/d1
• frac (double) n1/ (double) d1
• frac (double) n1/d1

6
Exercises

• If squaring 10-20 gives a result of 0, the type
  of error that has occurred is called ..
• Evaluate the following expressions if
  x10.5,y7.2, m5, and n2
• x/(double) m
• (double) (n/m) y
• Write a c program to display the characters from
  character to the character Z.
• Evaluate (int) D (int) A, (char) ((int)
  C 2), (int) 6 (int) 7
• Write a C program to accumulate the weekday hours
  worked.
• You need to use an enum type loop counter day_t.
  
  
  
  
  
  
  
  
  
  
  
  
• Use a function print_day to display a string
  corresponding to a value of type day_t.

7
Exercises

• What does the segment print ?
• For(ch(int) dchlt(int) n ch3)
• printf(c,(char)ch)
• printf(\n)
• Which of the following can be an enumeration
  constant ? 1-an integer 2-a floating-point
  number, an identifier, a string value.
• What is wrong with the following enumerated type
  definition ? typedef enum2,3,5,7,11,13
  prime_t
• Consider the enumerated type definition
• typedef enumfresh,soph,jr,sr class_t
• What is the value of each of the following ?
• A-(int) sr, B-(class_t) 0, C- (class_t)
  ((int)soph1)