import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        String length = s.next();
        String targetNum = s.next();
        String stringValue = s.next();
        int a = Integer.parseInt(targetNum) - 1;
        char[] carVals = stringValue.toCharArray();
        carVals[a] =
                Character.toLowerCase(carVals[a]);
        System.out.println(String.valueOf(carVals));
    }
} import java.util.Scanner; Scanner java.util public class Main {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        String length = s.next();
        String targetNum = s.next();
        String stringValue = s.next();
        int a = Integer.parseInt(targetNum) - 1;
        char[] carVals = stringValue.toCharArray();
        carVals[a] =
                Character.toLowerCase(carVals[a]);
        System.out.println(String.valueOf(carVals));
    }
} Main public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        String length = s.next();
        String targetNum = s.next();
        String stringValue = s.next();
        int a = Integer.parseInt(targetNum) - 1;
        char[] carVals = stringValue.toCharArray();
        carVals[a] =
                Character.toLowerCase(carVals[a]);
        System.out.println(String.valueOf(carVals));
    } main {
        Scanner s = new Scanner(System.in);
        String length = s.next();
        String targetNum = s.next();
        String stringValue = s.next();
        int a = Integer.parseInt(targetNum) - 1;
        char[] carVals = stringValue.toCharArray();
        carVals[a] =
                Character.toLowerCase(carVals[a]);
        System.out.println(String.valueOf(carVals));
    } Scanner s = new Scanner(System.in); s new Scanner(System.in) String length = s.next(); length s.next() s.next s String targetNum = s.next(); targetNum s.next() s.next s String stringValue = s.next(); stringValue s.next() s.next s int a = Integer.parseInt(targetNum) - 1; a Integer.parseInt(targetNum) - 1 Integer.parseInt(targetNum) Integer.parseInt Integer targetNum 1 char[] carVals = stringValue.toCharArray(); carVals stringValue.toCharArray() stringValue.toCharArray stringValue carVals[a] =
                Character.toLowerCase(carVals[a]) carVals[a] carVals a Character.toLowerCase(carVals[a]) Character.toLowerCase Character carVals[a] carVals a System.out.println(String.valueOf(carVals)) System.out.println System.out System System.out String.valueOf(carVals) String.valueOf String carVals String[] args args public class Main {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        String length = s.next();
        String targetNum = s.next();
        String stringValue = s.next();
        int a = Integer.parseInt(targetNum) - 1;
        char[] carVals = stringValue.toCharArray();
        carVals[a] =
                Character.toLowerCase(carVals[a]);
        System.out.println(String.valueOf(carVals));
    }
} public class Main {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        String length = s.next();
        String targetNum = s.next();
        String stringValue = s.next();
        int a = Integer.parseInt(targetNum) - 1;
        char[] carVals = stringValue.toCharArray();
        carVals[a] =
                Character.toLowerCase(carVals[a]);
        System.out.println(String.valueOf(carVals));
    }
} Main
import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        String length = s.next();
        String targetNum = s.next();
        String stringValue = s.next();
        int a = Integer.parseInt(targetNum) - 1;
        char[] carVals = stringValue.toCharArray();
        carVals[a] =
                Character.toLowerCase(carVals[a]);
        System.out.println(String.valueOf(carVals));
    }
}
