#include <Servo.h>
Servo s1;
Servo s2;
Servo s3;
Servo s4;
void setup() {
  s1.attach(3);
  s2.attach(6);
  s3.attach(10);
  s4.attach(5);
  

}

void loop() {
for(int i=0;i<=180;i++){
  s1.write(i);
  s2.write(i);
  s3.write(180-i);
  s4.write(180-i);
 delay(2);
}

for(int j=180;j>=0;j--){
  s1.write(j);
  s2.write(j);
  s3.write(180-j);
  s4.write(180-j);
 delay(2);
}

}