1-D Array

One Dimensional Array in C

• We can declare an array in the c language in the following way.

data_type array_name[array_size];  

• Now, let us see the example to declare array.

int marks[5];  

• Here, int is the data_type, marks is the array_name and 5 is the array_size.

1-D Array

Initialization of C Array

• A simple way to initialize array is by index. Notice that array index starts from 0 and ends with [SIZE - 1].

marks[0]=2;//initialization of array  
marks[1]=8;  
marks[2]=7;  
marks[3]=6;  
marks[4]=0;  

Array Declaration

C array example

#include <stdio.h>    
#include <conio.h>    
void main(){    
int i=0;  
int marks[5];//declaration of array  
clrscr();    
marks[0]=80;//initialization of array  
marks[1]=60;  
marks[2]=70;  
marks[3]=85;  
marks[4]=75;  
//traversal of array  
for(i=0;i<5;i++){    
printf("%d \n",marks[i]);  
}//end of for loop  
getch();    
}

Output
80
60
70
85
75

C Array: Declaration with Initialization

• We can initialize the c array at the time of declaration. Let's see the code.

int marks[5]={20,30,40,50,60};  

• In such case, there is no requirement to define size. So it can also be written as the following code.

int marks[]={20,30,40,50,60};  

• Let's see the full program to declare and initialize the array in C.

#include <stdio.h>    
#include <conio.h>    
void main(){    
int i=0;  
int marks[5]={20,30,40,50,60};//declaration and initialization of array  
clrscr();    
//traversal of array  
for(i=0;i<5;i++){    
printf("%d \n",marks[i]);  
}  
getch();    
}    
Output
20
30
40
50
60

// Program to take 5 values from the user and store them in an array and printing the elements stored in the array.

#include <stdio.h>

#include<conio.h>

void main() 

{

  int values[5];

  printf("Enter 5 numbers ");

  // taking input and storing it in an array

  for(int i = 0; i < 5; ++i) {

     scanf("%d", &values[i]);

  }

  printf("Displaying numbers: ");

  // printing elements of an array

  for(int i = 0; i < 5; ++i) {

     printf("%d\n", values[i]);

  }

  getch();

}

Expected Output:

Enter 5 numbers

7

9

8

4

6

Displaying numbers:

7

9

8

4

6