using System; public class Exercise16 { public static void Main() { string username, password; int ctr = 0; Console.Write("\n\nCheck username and password :\n"); Console.Write("N.B. : Default user name and password is :abcd and 1234\n"); Console.Write("------------------------------------------------------\n"); do { Console.Write("Input a username: "); username = Console.ReadLine(); Console.Write("Input a password: "); password = Console.ReadLine(); if(username != "abcd" || password != "1234") ctr++; else ctr=1; } while((username != "abcd" || password != "1234") && (ctr != 3)); if (ctr == 3) Console.Write("\nLogin attemp three or more times. Try later!\n\n"); else Console.Write("\nThe password entered successfully!\n\n"); } }