Here are some various bits of code you can use to accomplish this.
Create array
int[] histogram = new int[13];
Increment a position in the array
histogram[id]++;
Print histogram
System.out.println("Histogram of rolls:" );
printHistogram(histogram);
Here are some helper functions as well.
private void printHistogram(int[] array) {
for (int range = 0; range < array.length; range++) {
String label = range + " : ";
System.out.println(label + convertToStars(array[range]));
}
}
private String convertToStars(int num) {
StringBuilder builder = new StringBuilder();
for (int j = 0; j < num; j++) {
builder.append('*');
}
return builder.toString();
}
Code should be modified as needed.