import java.util.*; public class Main { static int i; public static void main(String[] args) { Scanner input = new Scanner(System.in); String s=""; while (true) { System.out.println("Input something to lexically analyze: "); s = input.nextLine(); analize(s); } } public static void analize(String s) { String t = "-1234567890_ abcdefjhijklmnopqrstuvwxyzABCDEFJHIJKLMNOPQRSTUVWXYZ"; char[] tt = t.toCharArray(); char[] cc = s.toCharArray(); int z = 1,i = 0,j = 0; for (i = 0; i < cc.length; i++) { for (j = 0; j < tt.length; j++) { if (cc[i] == tt[j]) { System.out.println("Token " + z + " = `" + cc[i] + "`"); z++; break; } } if (j > tt.length-1) { System.out.println("Invalid character " + (i + 1) + " (`" + cc[i] + "`) entered..."); } } } } ©