Primitive type:
- Variables are used to store data.
- Primitive variable can store only one value at a time.
For example,
| int main() { int a=5; a=10; a=20; printf(“a val : %d \n”, a); // prints – 20 return 0; } |
Array:
- Array is used to store more than one value but of same type.
- For example, storing 100 students’ average marks.
Array creation:
- In array variable declaration, we need to specify the size
- Array variable stores base address of memory block.
- Array elements store in consecutive memory location.
Process Array elements:
- Array memory locations must be accessed through their index.
- Index values starts from 0 to Size-1
How to access array elements?
- Array consists multiple values.
- We can simply use loops to process array locations.
| Reading | Printing |
| int i; for(i=0 ; i<5 ; i++) { scanf(“%d”, &marks[i]); } | int i; for(i=0 ; i<5 ; i++) { printf(“%d”, marks[i]); } |
Array as Local variable:
- Declare array variable inside the function.
- If the array variable is local, all locations initialize with garbage values.
| int main() { int arr[5], i; printf(“Array elements are : \n”); for(i=0 ; i<5 ; i++){ printf(“%d \n”, arr[i]); } return 0; } |
Array as Global variable:
- Declare array variable outside to all functions.
- Global array variable locations initialize with default values.
| int arr[5]; int main() { int i; printf(“Array elements are : \n”); for(i=0 ; i<5 ; i++){ printf(“%d \n”, arr[i]); } return 0; } |