Counts the number of uppercase letters, lowercase letters, and numbers in a string. __ Personal Practice

public class Stringtest {
public static void Main (string[] args) {
Encapsulating keyboard Input data
Scanner sc = new Scanner (system.in);
System.out.println ("Please enter a string:");
String line = Sc.nextline ();

Defining statistical variables
int big = 0;
int small = 0;
int number = 0;

  //length,charat
  for (int x = 0; x < line.length () + x + +) {
   //get each Characters
   char ch = line.charat (x);
   if (ch >= ' 0 ' && ch <= ' 9 ') {
    number++;
   } else if (ch >= ' A ' && ch <= ' Z ') {
    big++;
 &nb SP;&NBSP} else if (ch >= ' a ' && ch <= ' z ') {
    small++;
   }   }
  
  system.out.println ("The number of uppercase letters in the string appears:" +big);
  system.out.println ("The number of lowercase letters in the string appears:" +small); The number occurrences in the
  system.out.println ("string) are:" +number);
  
 }
}