
using Xunit;
using Xunit;
using System;
using System.IO;

namespace ConsoleApp {
    public class ProgramTests {
        [Fact(DisplayName = "Stops checking after correct password is entered (no if or break)")]
        public void StopsCheckingAfterCorrectPassword_NoIfOrBreak()
        {
            var sw = new StringWriter();
            Console.SetOut(sw);
            string[] attempts = {"wrong1", "letmein", "wrong2"};
            Program.SimulatePasswordAttempts("letmein", attempts, 3);
            string output = sw.ToString();
            Assert.Contains("Password entered: wrong1", output);
            Assert.Contains("Password entered: letmein", output);
            Assert.DoesNotContain("Password entered: wrong2", output);
            Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = true });
        }
        
        [Fact(DisplayName = "Prints success message when correct password is found (no if)")]
        public void PrintsSuccessMessage_NoIf()
        {
            var sw = new StringWriter();
            Console.SetOut(sw);
            string[] attempts = {"letmein"};
            Program.SimulatePasswordAttempts("letmein", attempts, 3);
            string output = sw.ToString();
            Assert.Contains("Access granted!", output);
            Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = true });
        }
        
        [Fact(DisplayName = "Prints account locked message if all attempts used (no if)")]
        public void PrintsAccountLockedMessage_NoIf()
        {
            var sw = new StringWriter();
            Console.SetOut(sw);
            string[] attempts = {"wrong1", "wrong2", "wrong3"};
            Program.SimulatePasswordAttempts("letmein", attempts, 3);
            string output = sw.ToString();
            Assert.Contains("Account locked. Too many failed attempts.", output);
            Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = true });
        }
        
        [Fact(DisplayName = "Decreases attempts after each wrong password (no if)")]
        public void DecreasesAttemptsAfterEachWrongPassword_NoIf()
        {
            var sw = new StringWriter();
            Console.SetOut(sw);
            string[] attempts = {"bad", "nope", "letmein"};
            Program.SimulatePasswordAttempts("letmein", attempts, 3);
            string output = sw.ToString();
            Assert.Contains("Incorrect password. Attempts left: 2", output);
            Assert.Contains("Incorrect password. Attempts left: 1", output);
            Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = true });
        }
        
        [Fact(DisplayName = "Prints attempts left after each incorrect try (no if)")]
        public void PrintsAttemptsLeftAfterEachIncorrectTry_NoIf()
        {
            var sw = new StringWriter();
            Console.SetOut(sw);
            string[] attempts = {"bad", "nope", "wrong"};
            Program.SimulatePasswordAttempts("letmein", attempts, 3);
            string output = sw.ToString();
            Assert.Contains("Incorrect password. Attempts left: 2", output);
            Assert.Contains("Incorrect password. Attempts left: 1", output);
            Assert.Contains("Incorrect password. Attempts left: 0", output);
            Console.SetOut(new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = true });
        }
    }
}

ProgramTests.cs

In this task:

- **`attempt`** is the current password guess from the `attempts` array, used for printing and comparison;
- **`remaining`** counts how many tries are left, decreasing after each wrong password;
- **`found`** is `true` when the correct password is entered, stopping the loop.

These variables let you manage attempts and stop the loop without using `if`, `else`, or `break`.

Note

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Challenge: Password Attempts

解答