Arrays are special variables which can hold more than one value under the same variable name, organised with an index. Arrays are defined using a very straightforward syntax:
/* defines an array of 10 integers */
int numbers[10];
Accessing a number from the array is done using the same syntax. Notice that arrays in C are zero-based, which means that if we defined an array of size 10, then the array cells 0 through 9 (inclusive) are defined. numbers[10] is not an actual value.
int numbers[10]; /* populate the array */ numbers[0] = 10; numbers[1] = 20; numbers[2] = 30; numbers[3] = 40; numbers[4] = 50; numbers[5] = 60; numbers[6] = 70; /* print the 7th number from the array, which has an index of 6 */ printf("The 7th number in the array is %d", numbers[6]);
Arrays can only have one type of variable, because they are implemented as a sequence of values in the computer’s memory. Because of that, accessing a specific array cell is very efficient.
Home Work
- Define an int array which includes 10 numbers.