What the hell did I do wrong

Ok, I understand java and C++, but I can't replicate this very strange error. So here, I ran this code onto my Arduino One. And, the ouput is a random spew of text and code, and I am CONFUSED!!!! May you please tell me what I did wrong?

#define echoPin 3
#define trigPin 4
#define armedPin 0 //RX
#define intrudedPin 1 //TX

int setDistance, distance;
boolean intruded = false;

int updateDistance(){
  int time = 0;
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(1000);
  digitalWrite(trigPin, LOW);
  time = pulseIn(echoPin, HIGH);
  distance = (time/2) / 29.1;
  Serial.println(distance + "cm");
  return distance;
}

void setup(){
  pinMode(echoPin, INPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(armedPin, OUTPUT);
  pinMode(intrudedPin, OUTPUT);
  Serial.begin(9600);
  Serial.println("You have 30 seconds till the security system engages!");
  for (int x = 3000; x > 0; x--){//Countdown till armed
    digitalWrite(armedPin, HIGH);
    digitalWrite(intrudedPin, HIGH);
    delay(10);
    digitalWrite(armedPin, LOW);
    digitalWrite(intrudedPin, LOW);
    Serial.println(x*100 + " seconds left!");
  }
  setDistance = updateDistance();
}

void loop(){
  if (!intruded){//Nothing has happened
    updateDistance();
    if (setDistance != distance){
      Serial.println("oh my, someone has tripped the wire!");
      Serial.println("You have 5 seconds till I claim I have been intruded into!");
      for (int x = 5000; x > 0; x--){
      digitalWrite(armedPin, HIGH);
      digitalWrite(intrudedPin, HIGH);
      delay(100);
      digitalWrite(armedPin, LOW);
      digitalWrite(intrudedPin, LOW);
      Serial.println(x*100 + " seconds left!");
      }
      updateDistance();
      if (setDistance != distance){
        intruded = true;
      }else{
        digitalWrite(armedPin, HIGH);
      }
  }else if (intruded){//Someone has intruded
  Serial.println("OH NO! SOMEONE HAS INTRUDED!\n INTRUDER ALERT\n INTRUDER ALERT\n INTRUDER ALERT");
  digitalWrite(intrudedPin, HIGH);
  digitalWrite(armedPin, LOW);
  while (true){
      delay(500000000);
    }
  }
}
}

a better explanation of what you want it to do and what it is doing would be awsome for us to look at

Run that program and you will have this result when looking at the serial monitor:

÷÷You have 30 seconds till the security system engages!
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You have 30 seconds till the security system engages!
d into!
bcm

Hello stasiomod,
Is there a way for you to change the armedPin and Intrudedpin pin definitions? like

#define armedPin 2
#define intrudedPin 5

I believe, using the TX and RX pins of your Arduino ONE is creating a communication conflict, though. Regards!

stasiomod,
Please, disregard my last comment. Just replace your two lines in setup and loop

Serial.println(x*100 + " seconds left!");

with the following:

Serial.print(x*100);
         Serial.println(" seconds left!");

Regards!

  while (true){
      delay(500000000);
    }

So, a fairly long delay, huh? And after that you reboot the system?

Please, disregard my last comment.

Why? It was perfectly valid, and explains a lot about the issues OP is having. Pins 0 and 1 can be used for IO OR Serial. They can not be used for both in the same sketch.