import java.util.ArrayList; import java.util.List; public class DigitRepeat { private double maxValue = 10; private List highestCtn = new ArrayList(); private List highestVal = new ArrayList(); public static void main(String[] args) { DigitRepeat dr = new DigitRepeat(); dr.find(10); for(int i = 0; i < dr.getHighestVal().size(); i++) System.out.println("Value: " + dr.getHighestVal().get(i) + " | Division: 1/" + dr.getHighestVal().get(i) + " | Count: " + dr.getHighestCtn().get(i)); } public void find(int max){ this.maxValue = max; char[] curr = new char[0]; for(int i = 2; i <= this.maxValue; i++){ curr = getAfterDigit((double)1/i); detectRepeats(curr, i); } } private char[] getAfterDigit(double input){ String strVal = String.valueOf(input); strVal = strVal.substring(strVal.indexOf(".") + 1); return strVal.toCharArray(); } private void detectRepeats(char[] digits, int val){ int highest = 0; int count = 0; //escape if to less digits, should be more than highest * 2 if(highestCtn.size() > 0 && digits.length < highestCtn.get(0).intValue() * 2) return; for(int i = 0; i < digits.length; i++){ for(int j = i + 1; j < digits.length; j++){ count = 0; //reset count on each start over if(digits[i] == digits[j]){ count++; for(int k = 1; k < j-i && k+j < digits.length; k++){ if(digits[i+k] == digits[j+k]){ if(digits[i+k] != digits[i+k-count]) count++; else break; //assume it's periodic }else break; //no further accordance } } if(count > highest) highest = count; } } prepareResult(highest, val); } private void prepareResult(int highest, int val){ if(highestCtn.size() == 0){ highestCtn.add(highest); highestVal.add(val); }else{ if(highestCtn.get(0).intValue() <= highest){ if(highestCtn.get(0).intValue() < highest){ highestCtn.clear(); highestVal.clear(); } highestCtn.add(highest); highestVal.add(val); } } } public List getHighestCtn(){ return this.highestCtn; } public List getHighestVal(){ return this.highestVal; } }

Java Digit Repeat (Multiple)