int[] data = {6, 14, 6, 14};
String[] labels = {"Spring", "Summer", "Fall", "Winter"};
int total;
float[] perc = new float[data.length];
color[] colors = {color(255,165,0), color(255,255,0), 
color(20,220,50), color(135,165,235)};

void setup(){
  size(500, 500);
  background(255);
  smooth();
  noLoop();
  
  int i;
  //compute the total population
  total=0;
  for(i=0; i<data.length; i++){
    total += data[i];
  }
  
  //compute percentages
  for(i=0; i<perc.length; i++){
    perc[i] = data[i]/total;
  }
}