How to send an entire array as an argument in C language?

An array is a group of related items that is stored with a common name.

Declaring array

The syntax for declaring an array is as follows −

datatype array_name [size];

Initialization

An array can be initialized in two ways, which are as follows −

• Compile time initialization.
• Runtime initialization.

An array can also be initialized at the time of declaration as follows −

int a[5] = {100,200,300,400,500};

Function

A function is a self-contained block that carries out a specific well-defined task. The two ways of passing the arrays as arguments to functions are as follows −

• Sending an entire array as an argument to function.

• Sending the individual elements as argument to function.

Now, let us understand how to send an entire array as an argument to function in C language.

Sending an entire array as argument to function

• To send an entire array as argument, try to send the array name in the function call.

• To receive an entire array, an array must be declared in the function header.

Example 1

Refer an example given below −

#include<stdio.h> main ( ){    void display (int a[5]);    int a[5], i;    clrscr( );    printf ("enter 5 elements");    for (i=0; i<5; i++)       scanf("%d", &a[i]);    display (a); // Sending entire array ‘a’ using array name    getch( ); } void display (int a[5]) {//receiving entire array    int i;    printf ("elements of the array are");    for (i=0; i<5; i++)       printf("%d ", a[i]); }

Output

When the above code is compiled together and executed, it produces the following result −

Enter 5 elements 10 20 30 40 50 Elements of the array are 10 20 30 40 50

Example 2

Following is the C program to print the elements in a reverse order from the array −

#include<stdio.h> void main(){    //Declaring the array - run time//    int array[5],i;    void rev(int array[5]);    //Reading elements into the array//    printf("Enter elements into the array: 
");    //For loop//    for(i=0;i<5;i++){       //Reading User I/p//       printf("array[%d] :",i);       scanf("%d",&array[i]);    }    //Displaying reverse order of elements in the array//    printf("The elements from the array displayed in the reverse order are : 
");    rev(array); // Sending entire array ‘a’ using array name    getch(); } void rev(int array[5]){ //receiving entire array    int i;    for(i=4;i>=0;i--){       //Displaying O/p//       printf("array[%d] :",i);       printf("%d
",array[i]);    } }

Output

When the above program is compiled together and executed, it produces the following result −

Enter elements into the array: array[0] :23 array[1] :34 array[2] :12 array[3] :56 array[4] :12 The elements from the array displayed in the reverse order are: array[4] :12 array[3] :56 array[2] :12 array[1] :34 array[0] :23