#include <Servo.h>

Servo myservo;  
int potpin = 0;  
int val;    

void setup() {
  myservo.attach(9);  
}

void loop() {
  val = analogRead(potpin);           
  val = map(val, 0, 1023, 0, 180);     
  myservo.write(val);                 
  delay(15);                          
}