median filter for arduino, uses bubble sort

gistfile1.txt

//  medianFilter filter;
//  filter.addValue(5);
//  filter.addValue(3);
//  filter.addValue(2);
//  filter.addValue(100);
//  filter.addValue(9);
//  Serial.println(filter.getMedian());
//  
//  filter.addValue(100);
//  Serial.println(filter.getMedian());
//  prints 5, 9

#define NUM_VALS_MEDIAN 5

class medianFilter {

  public: 

  float vals[NUM_VALS_MEDIAN];
  float valsSorted[NUM_VALS_MEDIAN];
  boolean firstVal;

  medianFilter(){
    firstVal = true;
  }

  void addValue(float val){
    if (firstVal == true){
      for (int i = 0; i < NUM_VALS_MEDIAN; i++) valsSorted[i] = val;
      for (int i = 0; i < NUM_VALS_MEDIAN; i++) vals[i] = val;
    } 
    else {
      for (int i = 1; i < NUM_VALS_MEDIAN; i++) vals[i-1] = vals[i];
      vals[NUM_VALS_MEDIAN-1] = val;
      for (int i = 0; i < NUM_VALS_MEDIAN; i++) valsSorted[i] = vals[i];
      // sort array
      bubbleSort();
    }
    firstVal = false;
  }
  
  float getMedian(){
     return valsSorted[ (int)floor(NUM_VALS_MEDIAN/2) ];
  }

  void bubbleSort() {
    int out, in;
    float swapper;
    for(out=0 ; out < NUM_VALS_MEDIAN; out++) {  // outer loop
      for(in=out; in<NUM_VALS_MEDIAN; in++)  {  // inner loop
        if( valsSorted[in] > valsSorted[in+1] ) {   // out of order?
          // swap them:
          swapper = valsSorted[in];
          valsSorted [in] = valsSorted[in+1];
          valsSorted[in+1] = swapper;
        }
      }
    }
  }
};

Hey, you gonna corrupt memory by line 55 because in can be NUM_VALS_MEDIAN-1