# 1 Dimensional Array in C

## 1D Array

1D Array is defined as the continuous block of memory in which a similar data type is stored. 1D Array indexing starts with size 0 and ends with size -1. The size of the 1D array is fixed and it is stored in static memory.

### Syntax:

`  [arr_size]={value 1, value 2, value 3,…,value n-1};`

### Array Declaration

Declaration of 1D Array consists of any data type and it can be declared by any random name or any random variable.

### Syntax:

`int arr[10]; // Here int is the data type of array.// arr is the name of array.// 10 is the size of array.`

### Array Initialization

In 1D Array, All the elements consist of garbage value at initial time but it can be explicitly initialized during declaration.

### Syntax:

`  [arr_size]={value 1, value 2, value 3,…,value n-1};`

### Accessing of elements in 1D Array:

In 1D Array elements are accessed by putting the array name and index value inside square brackets.

### Syntax:

`<arr_name>[index];`

### Rules for 1D Array Declaration:

• In 1D array we must have to declare the array variable.
• 1D Array stores the data in contiguous memory locations.
• 1D Array  should be a list of similar data types.
• The size of the 1D array should be fixed.
• 1D Array should be stored in static memory.
• 1D Array indexing starts with size 0 and ends with size -1.
• In 1D Array declaration of array size within the bracket is not necessary.
• In 1D Array it must include the variable name  and data type while declaring any arrays .

### Example 1

Run
```#include <stdio.h>
int main() {
int arr[5] = {1,3,5,7,9};
printf("The elements of arrays are :");
for(int i=0; i<5; i++){
printf(" %d",arr[i]);
}
return 0;
}
```

### Output:

`The elements of arrays are : 1 3 5 7 9`

### Example 2

Run
```#include <stdio.h>
int main() {
int arr[12] = {1,3,5,7,9,10,12,14,23,22,33,35};
printf("The even elements in arrays are :");
for(int i=0; i<12; i++){
if(arr[i]%2==0) printf(" %d",arr[i]);
}
return 0;
}```

### Output

`The even elements in arrays are : 10 12 14 22`

### Example 3

Run

```#include
int main() {
int arr[11] = {3,5,7,9,10,12,14,23,22,33,35};
for(int i=0; i<11; i++){
if(i==0){
printf("First element of array : %d\n",arr[i]);
}
else if(i==4) {
printf("Fifth element of array : %d\n", arr[i]);
}
else if(i==10){
printf("Last element of the array : %d", arr[i]);
}
}
return 0;
}```

### Output

```First element of array : 3
Fifth element of array : 10
Last element of the array : 35```

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