I googled the error message and all the sources I could find say that that means that there is a missing library. The code does not need any librarys as far as I know , but any advise helps, thanks! (The code is supposed to wait until 3 buttons have been pressed, and check if there is a combination that equals the pattern of buttons pressed, if there is, a pin is set to high. The code is not entirely done but it won't let me upload to test it.)

here is the code:

int A = 0;

int B = 0;

int C = 0;

int D = 0;

int E = 0;

int F = 0;

int G = 0;

int H = 0;

​

void setup() {

pinMode(A0 , OUTPUT);

pinMode(A1 , OUTPUT);

pinMode(A2 , OUTPUT);

pinMode(12, INPUT_PULLUP);

pinMode(11, INPUT_PULLUP);

pinMode(10, INPUT_PULLUP);

}

​

void loop() {

while (A < 3) {

if (digitalRead(12) == HIGH) {

B = E 1;

F = F 1;

}

if (digitalRead(11) == HIGH) {

C = E 1;

F = F 1;

}

if (digitalRead(10) == HIGH) {

D = E 1;

F = F 1;

}

​

}

​

if (A == 1 && (B == 2 && (C == 3))) {

analogWrite(1 = HIGH);

}

​

if (C == 1 && (B == 2 && (A == 3)))

{

analogWrite(2 = HIGH);

}

​

}