Count numbers, letters, spaces, and other characters in a string

public class Calcharnumbers {public
	static void Main (string[] args) {
		System.out.println ("Please enter a string:");
		Scanner sc = new Scanner (system.in);
		String str = Sc.nextline ();//This Must be sc.nextline (); The input string in Java can also be sc.next (), but reading a space in this way stops
		int alphanum = 0;
		int spacenum = 0;
		int digtnum = 0;
		int othernum = 0;
		for (int i=0;i<str.length (); i++) {
			if (Str.charat (i) >= ' 0 ' &&str.charat (i) <= ' 9 ') {
				digtnum+ +;
			} else if ((Str.charat (i) >= ' a ' &&str.charat (i) <= ' z ') | | (Str.charat (i) >= ' A ' &&str.charat (i) <= ' Z ')) {
				alphanum++;
			} else if (Str.charat (i) = = ') {
				spacenum++
			} else{
				othernum++
			}
		}
		System.out.println ("Letter:" +alphanum+ ", Number:" +digtnum+ ", Space:" +spacenum+ ", other characters:" +othernum);
	}

The following are implemented with regular expressions:

Import Java.util.Scanner;
Import Java.util.regex.Matcher;
Import Java.util.regex.Pattern;
Counts	the number of letters, spaces, numbers, and other characters in a string public
class Calcharnumbers {public
	static void Main (string[] args) {
		System.out.println ("Please enter a string:");
		Scanner sc = new Scanner (system.in);
		String s = sc.nextline ();
		String regex1 = "[a-z| A-z] ";
		String regex2 = "[0-9]";
		Calcharnumbers C = new Calcharnumbers ();
		int a1 = C.string (S, regex1);
		System.out.println ("Number of digits:" +a1);
		int a2 = c.string (S, regex2);
		System.out.println ("Number of Letters:" +A2);
		int a3 = c.string (S, "");
		System.out.println ("Number of Spaces:" +A3);
		int a4 = s.length ()-a1-a2-a3;
		System.out.println ("Number of other characters:" +a4);
	}
	 public int string (string s, string patterns) {
		    pattern p = pattern.compile (patterns);//To compile the given regular expression into the schema.
		    Matcher m = P.matcher (s);//create a match between the given input and this pattern.
		    int i = 0;
		    while (M.find ()) {//attempts to find the next subsequence of the input sequence that matches the pattern.
		      i++;
		    }
		    return i;
		  }
}