reading and writing to the serial port

i have 'frankensteined' two sketches together. the first one i'm using to read what's happening on my analog ports. the other i am not as familiar with, which involves writing data to the serial port using max msp, and then writes the values to the LED.

off the bat, using parseInt slows down all the analog reading. i just don't know much about what is happening here.

  Reads an analog input on pin 0, prints the result to the serial monitor.
  Attach the center pin of a potentiometer to pin A0, and the outside pins to +5V and ground.

 This example code is in the public domain.

const int redPin = 11;
const int greenPin = 10;
const int bluePin = 9;

// the setup routine runs once when you press reset:
void setup() {
  // initialize serial communication at 9600 bits per second:

    pinMode(redPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  pinMode(bluePin, OUTPUT);

// the loop routine runs over and over again forever:
void loop() {
  // read the input on analog pin 0:
  int sensorValue =  analogRead(A0);
    int sensorValue2 =  analogRead(A1);
      int sensorValue3 =  analogRead(A2);
        int sensorValue4 =  analogRead(A7);
          int sensorValue5 =  analogRead(A6);
            int sensorValue6 =  analogRead(A5);
              float sensorValue7 =  analogRead(A4);
 // print out the value you read:

 //begin frankenstein

  // look for the next valid integer in the incoming serial stream:
  // this section slows down all the analog reading off the bat
    int red = Serial.parseInt();
    // do it again:
    int green = Serial.parseInt();
    // do it again:
    int blue = Serial.parseInt();

       if ( == '\n') {
      // constrain the values to 0 - 255 and invert
      // if you're using a common-cathode LED, just use "constrain(color, 0, 255);"
//      red = 255 - constrain(red, 0, 255);
  //    green = 255 - constrain(green, 0, 255);
    //  blue = 255 - constrain(blue, 0, 255);

      // fade the red, green, and blue legs of the LED:
  //    analogWrite(redPin, red);
    //  analogWrite(greenPin, green);
     // analogWrite(bluePin, blue);

      // print the three numbers in one string as hexadecimal:
      //Serial.print(red, HEX);
      //Serial.print(green, HEX);
      //Serial.println(blue, HEX);

// end frankenstein

  Serial.print("a1 ");
  Serial.print("a2 ");
  Serial.print("a3 ");
  Serial.print("a4 ");
  Serial.print("a5 ");
  Serial.print("a6 ");
   Serial.print("a7 ");

  delay(1);        // delay in between reads for stability

Have a look at Serial Input Basics - simple reliable non-blocking ways to receive data.