4. Minimum Swaps.java

import java.io.*;
import java.util.*;

public class Solution {
    
    static int minimumSwaps(int[] array) {
        int n = array.length - 1;
        int minSwaps = 0;
        for (int i = 0; i < n; i++) {
            if (i < array[i] - 1) {
                swap(array, i, Math.min(n, array[i] - 1));
                minSwaps++;
                i--;
            }
        }
        return minSwaps;
    }

    private static void swap(int[] array, int i, int j) {
        int temp = array[i];
        array[i] = array[j];
        array[j] = temp;
    }

    private static final Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) throws IOException {
        BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH")));

        int n = scanner.nextInt();
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

        int[] arr = new int[n];

        String[] arrItems = scanner.nextLine().split(" ");
        scanner.skip("(\r\n|[\n\r\u2028\u2029\u0085])?");

        for (int i = 0; i < n; i++) {
            int arrItem = Integer.parseInt(arrItems[i]);
            arr[i] = arrItem;
        }

        int res = minimumSwaps(arr);

        bufferedWriter.write(String.valueOf(res));
        bufferedWriter.newLine();

        bufferedWriter.close();

        scanner.close();
    }
}