Need Help Understanding Error

Hi, I am trying to write code for a 'heat alarm' system just for fun. I am planning for two events to occur when the thermistor senses that the temperature rises above a certain point. I'm trying to get an LED to pulse from 0 to 255 and back to 0 with a delay of 10 milliseconds between each increment. I am also planning to make a piezo buzzer turn on for a second and then off for another at the same time. I tried doing this with multiple methods, but I realized that they ran one after another. So now I'm trying to do it with one while loop with an integer called switch. However, when I try to run it, I get some errors I don't understand.
Here's my code:

const int LED = 9;
const int Buzzer = 6;
int val = 0;
const int switch = 0;

void setup(){
  pinMode(LED, OUTPUT);
  pinMode(Buzzer, OUTPUT);
  Serial.begin(9600);
}

void loop(){
  val = analogRead(0);
  Serial.println(val);
  
  while(val > 540){
    for(int x = 0; x < 255; x++){ 
      analogWrite(LED, x);
      delay(10);
      if(x % 100 == 0){
        if(switch == 0){
          switch = 1;
        }
        else{
          switch = 0;
        }
      }
      if(switch == 1){
        digitalWrite(Buzzer, HIGH);
      }
      else{
        digitalWrite(Buzzer, LOW);
      }
    }
    val = analogRead(0);
    Serial.println(val);
  }
}

The errors i'm getting:

sketch_jun14a:4: error: expected unqualified-id before 'switch'
sketch_jun14a.ino: In function 'void loop()':
sketch_jun14a:21: error: expected primary-expression before 'switch'
sketch_jun14a:21: error: expected )' before 'switch' sketch_jun14a:22: error: expected (' before '=' token
sketch_jun14a:25: error: expected (' before '=' token sketch_jun14a:28: error: expected primary-expression before 'switch' sketch_jun14a:28: error: expected )' before 'switch'

Thanks for all help in advance!

you cant use "switch" becz it is a reserved word like "int"

Ohh.... Its for the switch() logic statement right? Thanks so much!

You may find this 3-band tri-color temperature code of interest. For the t85 but can be easily run on UNO, just remove the power saving stuff.

http://www.hackster.io/rayburne/hot-yet

Ray