‘C’ LANGUAGE PRESENTATION

 C language was introduced by Dennis Ritchie..  It is a programming language, which can make a interaction between user and a machine..  It is a basic programming language & it is recognized as a high level language..  It was developed as a software development programming language in ‘AT&T Bell’ labs in between 1969 &

 Program means nothing but doing a task at a time at a particular place..  We need three steps to construct a program..  In C language we construct a program which consists of input, procedure& output..

 Firstly to construct a program we have to decide an exact output..  Then as a next step, we have to give an Input according to the Output..  Now next to the procedure..  Now the required Output will be displayed in EXE file by compiling..

 Compile :- Machine does not understand the common language which is entered in the program..  Compiler translates the source code (used in the program) to binary code( Machine code)..  It checks and displays whether the program contains any errors..

 After compiling the program, run is necessary..  If there are no errors, then we can run the program..  By running, the program can be executed..  Then the written program’s output can be displayed in EXE file..

 Function is nothing but ‘Working’..  Functions to a program is just like bricks to construct a wall..  Function in C is defined as a set of related statements..  Every function can perform its particular task..  Printf(); scanf(); getch() ect are some functions used in a program….

 In C language we have one basic condition..  Every function will be executed by other function..  Main function is defined as “Over all executable function.”..  So it could be mentioned in between header files and procedure..

 These are placed at the top of the program..  Header files contains the perfect definitions of functions..  In C, the program always executes from top to bottom..  It is difficult to mention these files above every function, so these files are placed at the top of the program..

 In C language we can use loops to repeatedly execute the same procedure..  There are different kinds of loops in C..  For, while, do-while are the 3 loops used in C program..  A loop begins with a open brace bracket ‘{‘ and ends with closed brace bracket ‘}’..

 For loop contains three indexes..  First one is for initialization..  Second one is for limiting..  Third one is for increment or decrement..  The given procedure in For loop is can be executed up to the limit which has mentioned in second index..

 While is used to repeat the procedure as For loop..  In while loop we need to mention one condition to repeat a procedure..  The program will be executed up to the mentioned condition is not to be satisfied..

 In while loop the procedure will be stopped, when the condition doesn’t satisfy..  In this loop, the procedure will be executed even for a single time though the given condition is not true..

 Primary data types could be of three varieties..  They are Characters, Integers and Floats..  They can derive many data types from these three types..  They can hold elements and keep those onto the location called Memory Blocks..  Data types have some capacity to hold those elements..  Every memory block have it’s particular location..

 A Character could be an Unsigned Char or a Signed Char..  The range of characters is from -127 to  A Signed char can have the range as same as the Ordinary char..  An Unsigned char has a range from 0 to 255..

 The range of an Integer constant depends upon the compiler..  For a 16 bit compiler like Turbo C or Turbo C++ the range is to  An int could be a short Int or a long Int..  Shorts are never bigger than ints..  Ints are never bigger than Longs..

 They can allow float values..  A float occupies 4 bytes in memory..  It’s range from -3.4e38 to +3.4e38..  If this is insufficient, then C offers a Double data type that occupies 8 bytes in memory and has a range from -1.7e308 to +1.7e308..

 Array is defined as collection of elements of same data type..  We can enter the number of elements of similar type onto one memory block by making some partitions, just like partitions of various rooms in a home..  First we need to decide the size of memory block and then we can enter those elements..

 When we use array for construct a program, firstly we need to decide the size of it..  After that we can not change it’s size while we runs the program..  Suppose, if the number of elements is less than the number of partitions of an array, then the remaining partitions can be wasted..  If the number of elements is greater than the size of an array then it will be collapsed..

 Structure is defined as the group of various data types..  We can make a group of various data types and we can give one name to that structure..  It can be useful when the data could be stored about various things or about various purposes..

By U.Susmitha Haritha Patil& K.Samatha.