cs146/03-labInsertionSort/Assignment.java

package labInsertionSort;

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

class Assignment {
    private static void insertionSort(int[] arr) {
        for (int i = 1; i < arr.length; i++) {
            int val = arr[i];
            int j = i-1;
            while (j >= 0 && arr[j] > val) {
                arr[j+1] = arr[j];
                j--;
            }
            arr[j+1] = val;

            // Print the subarray at the end of each iteration to show invariant
            printSubArray(arr, i);
        }
    }

    // Print the subarray arr[0, 1, ..., j] with ";" after elements
    private static void printSubArray(int[] arr, int j) {
        for (int index = 0; index < arr.length && index <= j; index++) {
            System.out.print(arr[index]);
            System.out.print(";");
        }
        System.out.println();
    }

    public static void run(String inputPath) {
        int[] sequence;
        int arraySize = 1;

        try (BufferedReader br = new BufferedReader(new FileReader(inputPath))) {
            // Get the size of the sequence
            arraySize = Integer.parseInt(br.readLine());
            sequence = new int[arraySize];

            // Read the sequence
            for (int i = 0; i < arraySize; i++) {
                sequence[i] = Integer.parseInt(br.readLine());
            }

            // Perform insertion sort in-place
            insertionSort(sequence);

        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}