It is a collection of elements having same data type, It is a fixed-size sequential collection of elements. An array element occupies contiguous memory locations.
C supports a special kind of data type called an array.
The element of an array is accessed by an index number. The index number contained within square brackets is also known as subscript.
Types of Arrays The arrays in C language can be classified in to following two categories :
(1) Single or One dimensional array
(2) Multidimensional array
The single dimensional array may have one row or one column while multidimensional array has one or more rows and one or more columns. The number of rows and columns are specified by user as per the program requirement. Declaration of Single Dimensional Array
To declare an array in C language, we specify the type of data which we want to store in the elements and the number of elements to be stored in an array as follows:
datatype
arrayname ( size );
datatype: It specify the type of elements that an array stores. If we want to store characters in an array then type of an array is 'char'. In the same way to store integers, type of an array is 'int'. The datatype can be any valid C language data type.
arrayname: This is the name given to an array variable by the programmer. It can be any string but it is usually suggested that some meaningful name should be given to an array. The array name should be in context with what is being stored in that array in a program.
size: The value of size indicates the number of elements the array can stores. The size must be an integer constant greater than zero.
(1) What happens if a C program tries to access a value from an array element whose subscript exceeds the size of array ?
(a) The element will be set to 0.
(b) The compiler would report an error.
(c) The program may crash or gives garbage data.
(d) The array size increases automatically.
(2) What will be the output of following program segment?
int num[5] = {1, 2, 3, 4, 5};
int i, j;
i = num[1];
j = num[2];
printf("%d, %d, %d", i, j, num[0]);
(a) 1, 2, 3
(b) 2, 3, 1
(c) 1, 2, 0
(d) 3,4,5
(3) What will be the output of following program segment ?
int num[5] = {1, 2, 3};
printf("%d, %d", num[0], num[3]);
(a) 1, 2
(b) 1, 0
(c) 1, 3
(d) 2,3