const int PinKey = 3;
const int PinLed = 2;
bool      ActLed = 0;

void setup(){
    pinMode( PinLed, OUTPUT );
    pinMode( PinKey, INPUT );
}
void loop(){
   
    if( digitalRead(PinKey)){
         ActLed = !ActLed;
        digitalWrite(PinLed, ActLed);
        while(digitalRead(PinKey)){
             delay(30);;
        }
        
    }
}