aaaa

const int a = A0;
int l = 0;
float t = 0.0;

void setup() {
  Serial.begin(9600);
  pinMode(a, INPUT);

}

void loop() {
  l = analogRead(a);
  t = l * 5.0 / 1024.0;
  Serial.println(t);
  delay(100);
}