IR Sensor arduino

// Simple Proximity Sensor using Infrared

 int IRpin = A5;               // IR photodiode on analog pin A0
 int IRemitter = 5;            // IR emitter LED on digital pin 2
 int ambientIR;                // variable to store the IR coming from the ambient
 int obstacleIR;               // variable to store the IR coming from the object
 int value[10];                // variable to store the IR values
 int distance;                 // variable that will tell if there is an obstacle or not
 int prevDistance = -1;

 int brightness = 0;

 const int measurementsCount = 2;
 int brightnessArr[measurementsCount];
 int currentPoint = 0;

 void setup() {
   Serial.begin(9600);         // initializing Serial monitor
   pinMode(IRemitter,OUTPUT);  // IR emitter LED on digital pin 2
   digitalWrite(IRemitter,LOW);// setup IR LED as off
 }

 void loop() {
   distance = readIR(5);

   brightness = map(distance, 0, 150, 0, 150);

   analogWrite(10, brightness);

   delay(10);
 }

 int readIR(int times) {
   int x, r;

   for(x=0; x<times; x++) {
     digitalWrite(IRemitter,LOW);    // turning the IR LEDs off to read the IR coming from the ambient
     delay(2);                       // minimum delay necessary to read values
     ambientIR = analogRead(IRpin);  // storing IR coming from the ambient

     digitalWrite(IRemitter,HIGH);   // turning the IR LEDs on to read the IR coming from the obstacle
     delay(2);                       // minimum delay necessary to read values
     obstacleIR = analogRead(IRpin); // storing IR coming from the obstacle

     value[x] = ambientIR-obstacleIR;
   }

   for(int x=0;x<times;x++){         // calculating the average based on the "accuracy"
     distance+=value[x];
   }

   return(distance/times);           // return the final value
 }