Fix ftp to allow doctests

[NSachida]

Describe your change:

using System; using System.Diagnostics; namespace euler { class Problem51 { public static void Main(string[] args) { new Problem51().BruteForce(); } public void BruteForce() { Stopwatch clock = Stopwatch.StartNew(); int[][] fiveDigitPattern = get5digitPatterns(); int[][] sixDigitPattern = get6digitPatterns(); int result = int.MaxValue; for (int i = 11; i < 1000; i += 2) { //Only 1,3,7,9 are valid endings if (i % 5 == 0) continue; int[][] patterns = (i < 100) ? fiveDigitPattern : sixDigitPattern; for(int j = 0; j <patterns.GetLength(0); j++){ for(int k = 0; k <= 2; k++){ //Don't generate candidates with leading zero if (patterns[j][0] == 0 && k == 0) continue; int[] pattern = fillPattern(patterns[j], i); int candidate = generateNumber(k, pattern); if (candidate < result && isPrime(candidate)) { if (familySize(k, pattern) == 8) result = candidate; break; } } } } clock.Stop(); Console.WriteLine("First prime in the eight prime family is {0}", result); Console.WriteLine("Solution took {0} ms", clock.ElapsedMilliseconds); } private int familySize(int repeatingNumber, int[] pattern) { int familySize = 1; for (int i = repeatingNumber + 1; i < 10; i++) { if (isPrime(generateNumber(i, pattern))) familySize++; } return familySize; } private int[] fillPattern(int[] pattern, int number) { int[] filledPattern = new int[pattern.Length]; int temp = number; for (int i = filledPattern.Length - 1; 0 <= i; i--) { if (pattern[i] == 1) { filledPattern[i] = temp % 10; temp /= 10; } else { filledPattern[i] = -1; } } return filledPattern; } private int generateNumber(int repNumber, int[] filledPattern) { int temp = 0; for (int i = 0; i < filledPattern.Length; i++) { temp = temp * 10; temp += (filledPattern[i] == -1) ? repNumber : filledPattern[i]; } return temp; } private int[][] get5digitPatterns() { int[][] retVal = new int[4][]; retVal[0] = new int[]{1,0,0,0,1}; retVal[1] = new int[]{0,1,0,0,1}; retVal[2] = new int[]{0,0,1,0,1}; retVal[3] = new int[]{0,0,0,1,1}; return retVal; } private int[][] get6digitPatterns() { int[][] retVal = new int[10][]; retVal[0] = new int[] { 1, 1, 0, 0, 0, 1 }; retVal[1] = new int[] { 1, 0, 1, 0, 0, 1 }; retVal[2] = new int[] { 1, 0, 0, 1, 0, 1 }; retVal[3] = new int[] { 1, 0, 0, 0, 1, 1 }; retVal[4] = new int[] { 0, 1, 1, 0, 0, 1 }; retVal[5] = new int[] { 0, 1, 0, 1, 0, 1 }; retVal[6] = new int[] { 0, 1, 0, 0, 1, 1 }; retVal[7] = new int[] { 0, 0, 1, 1, 0, 1 }; retVal[8] = new int[] { 0, 0, 1, 0, 1, 1 }; retVal[9] = new int[] { 0, 0, 0, 1, 1, 1 }; return retVal; } private bool isPrime(int n) { if (n <= 1) return false; if (n == 2) return true; if (n % 2 == 0) return false; if (n < 9) return true; if (n % 3 == 0) return false; int counter = 5; while ((counter * counter) <= n) { if (n % counter == 0) return false; if (n % (counter + 2) == 0) return false; counter += 6; } return true; }

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

Please reopen this pull request once you commit the changes requested or make improvements on the code. If this is not the case and you need some help, feel free to seek help from our Gitter or ping one of the reviewers. Thank you for your contributions!