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

// The main method must be in a class named "Main".
class Main {
    public static void main(String[] args) {
        String txt = "banana";
        //minuscula
        // System.out.println(txt.toLowerCase());
        
        // conviete en mayucula
        // System.out.println(txt.toUpperCase());

        // convertir strin en un array de caracteres
        // char[] arrc = txt.toCharArray();
        // System.out.println(Arrays.toString(arrc));
        
        /*Para buscar index de primera poscion del caracter*/
        //obtiene la primera couencidencia
        // System.out.println(txt.indexOf("n"));
        
        //tambien puede contar la veces que aparece una cadena
        // int pos = txt.indexOf('a');
        // while (pos != -1) {
        //     System.out.println("a en posición: " + pos);
        //     pos = txt.indexOf('a', pos + 1);
        // }
        
        /**/
        // separa numeros de letras
        // String text = "hola123";
        // int index = text.indexOf("1");
        
        // String part1 = text.substring(0, index);
        // String part2 = text.substring(index);
        // System.out.println(part1);
        // System.out.println(part2);

        // System.out.println(txt.charAt(0));
        // System.out.println(txt.charAt(txt.length() -1));

        // txt = "Hola mundo";
        // System.out.println(txt.contains("Hola"));

        for (int i = 0; i < txt.length(); i++) {
            char c = txt.charAt(i);
            if(txt.indexOf(c) != i){
                continue;
            }
            int count = txt.length() - txt.replace(String.valueOf(c), "").length();
            System.out.println(c + " : " + count);
        }
        
    }

    

    
}

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