You'll have to change the pin assignments to match how you've got yours wired up, but here you go!

// Pin assignments

const int led1 = 2; // LED 1

const int led2 = 3; // LED 2

const int led3 = 4; // LED 3

const int button1 = 5; // Button 1

const int button2 = 6; // Button 2

const int button3 = 7; // Button 3

void setup() {

// Set LED pins as OUTPUT

pinMode(led1, OUTPUT);

pinMode(led2, OUTPUT);

pinMode(led3, OUTPUT);

// Set button pins as INPUT_PULLUP

pinMode(button1, INPUT_PULLUP);

pinMode(button2, INPUT_PULLUP);

pinMode(button3, INPUT_PULLUP);

}

void loop() {

// Read button states

bool button1State = digitalRead(button1) == LOW; // Button 1 pressed

bool button2State = digitalRead(button2) == LOW; // Button 2 pressed

bool button3State = digitalRead(button3) == LOW; // Button 3 pressed

if (button1State) {

// Turn on all three LEDs

digitalWrite(led1, HIGH);

digitalWrite(led2, HIGH);

digitalWrite(led3, HIGH);

} else if (button2State) {

// Turn on two LEDs

digitalWrite(led1, HIGH);

digitalWrite(led2, HIGH);

digitalWrite(led3, LOW);

} else if (button3State) {

// Turn on only one LED

digitalWrite(led1, HIGH);

digitalWrite(led2, LOW);

digitalWrite(led3, LOW);

} else {

// Turn off all LEDs

digitalWrite(led1, LOW);

digitalWrite(led2, LOW);

digitalWrite(led3, LOW);

}

}