Arrays

An array holds many values of the same type in one variable. Size is fixed after creation.

Arrays — fixed-size lists

An array holds many values of the same type in one variable. Size is fixed after creation.

Index starts at 0. Last index is length - 1. Access with arr[i].

Real-life example: An array is a row of lockers — each locker has a number (index). You cannot add a 11th locker without a new row.

Create and use arrays

int[] scores = {90, 85, 78, 92};
System.out.println(scores[0]);  // 90
System.out.println(scores.length); // 4

String[] names = new String[3];
names[0] = "Asha";
names[1] = "Rohan";
names[2] = "Priya";

Loop through arrays

Use for loop with index or enhanced for (for-each) to visit every element.

for-each is simpler when you only need values, not index.

Real-life example: for-each is like reading every name on a attendance sheet top to bottom without caring about roll number.

For-each and indexed loop

int[] nums = {10, 20, 30};

for (int n : nums) {
    System.out.println(n);
}

for (int i = 0; i < nums.length; i++) {
    System.out.println("Index " + i + ": " + nums[i]);
}