10/26

smooth输入（10个值平均值，新值与前9个值）

int readings[numReadings];

void loop() {

total= total - readings[readIndex];

readings[readIndex] = analogRead(inputPin);

total= total + readings[readIndex];

readIndex = readIndex + 1;

if (readIndex >= numReadings)

readIndex = 0;

average = total / numReadings;}