package calc;

import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class Euler {

	public static int sumProblem1() {
		int total = 0;
		for (int i = 0; i < 1000; i++) {
			if (i % 3 == 0 || i % 5 == 0) {
				total += i;
			}
		}
		return total;
	}

	public static int sumFibonacci() {
		int total = 0;
		int a = 0;
		int b = 1;

		while (b <= 4000000) {
			a += b;
			b = a - b;
			System.err.println(b);
			if (b % 2 == 0) {
				total += b;
			}
		}
		return total;
	}

	public static int primeFactor(long n) {
		for (int i = 2; i <= n; i++) {
			while (n % i == 0) {
				System.out.println(i);
				n /= i;
			}
		}
		return 0;
	}

	public static int reverse(int number) {
		int reverse = 0;
		int remainder = 0;
		do {
			remainder = number % 10;
			reverse = reverse * 10 + remainder;
			number = number / 10;
		} while (number > 0);
		return reverse;
	}

	public static int largestPalindromeProduct(List<Integer> drones) {
		int max = 0;
		for (int i = 10; i <= 999; i++) {
			for (int j = 10; j <= 999; j++) {
				if (i * j == reverse(i * j)) {
					if (i * j > max) {
						max = i * j;
					}
				}
			}
		}
		System.out.println(max);
		return 0;
	}

	public static int smallestEvenlyDivisible() {
		int num = 1;
		while (true) {
			boolean divisible = true;
			for (int i = 1; i <= 20; i++) {
				if (num % i != 0) {
					divisible = false;
				}
			}
			if (divisible) {
				return num;
			} else {
				num++;
			}
		}
	}

	public static int sumSquare() {
		int squareSum = 0;
		int sumSquare = 0;
		int sum = 0;
		for (int i = 1; i <= 100; i++) {
			squareSum += (int) Math.pow(i, 2);
		}
		for (int i = 1; i <= 100; i++) {
			sum += i;
		}
		sumSquare = (int) Math.pow(sum, 2);
		return sumSquare - squareSum;
	}

	public static boolean isPrime(long x) {
		long i = 2;
		if (x == 2) {
			return true;
		}
		while (x > i) {
			if (x % i == 0) {
				return false;
			}
			i++;
		}
		return true;
	}

	public static long nPrime(long n) {
		long count = 0;
		long i = 2;
		long nPrime = 0;
		while (count < n) {
			if (isPrime(i)) {
				count++;
			}
			nPrime = i;
			i++;
		}
		return nPrime;
	}

	public static int pythagoreanTriplet() {
		for (int c = 3; c < 1000; c++) {
			for (int b = c - 1; b > 2; b--) {
				for (int a = b - 1; a > 1; a--) {
					if (Math.pow(a, 2) + Math.pow(b, 2) == Math.pow(c, 2)) {
						System.out.println("A:" + a + " B:" + b + " C:" + c);
						if (a + b + c == 1000) {
							System.out.println("Resposta: " + a * b * c);
							return a * b * c;
						}
					}
				}
			}
		}

		return 0;
	}

	public static long greatestProduct(int pLength) {
		String bigNumber = "73167176531330624919225119674426574742355349194934"
				+ "96983520312774506326239578318016984801869478851843"
				+ "85861560789112949495459501737958331952853208805511"
				+ "12540698747158523863050715693290963295227443043557"
				+ "66896648950445244523161731856403098711121722383113"
				+ "62229893423380308135336276614282806444486645238749"
				+ "30358907296290491560440772390713810515859307960866"
				+ "70172427121883998797908792274921901699720888093776"
				+ "65727333001053367881220235421809751254540594752243"
				+ "52584907711670556013604839586446706324415722155397"
				+ "53697817977846174064955149290862569321978468622482"
				+ "83972241375657056057490261407972968652414535100474"
				+ "82166370484403199890008895243450658541227588666881"
				+ "16427171479924442928230863465674813919123162824586"
				+ "17866458359124566529476545682848912883142607690042"
				+ "24219022671055626321111109370544217506941658960408"
				+ "07198403850962455444362981230987879927244284909188"
				+ "84580156166097919133875499200524063689912560717606"
				+ "05886116467109405077541002256983155200055935729725"
				+ "71636269561882670428252483600823257530420752963450";

		long max = 0;
		for (int i = 0; i < bigNumber.length() - pLength; i++) {
			String set = bigNumber.substring(i, pLength + i);
			long product = 1;
			for (int j = 0; j < set.length(); j++) {
				product *= Character.getNumericValue(set.charAt(j));
			}
			if (product > max) {
				max = product;
			}
		}
		return max;
	}

	public static long sumPrime(long n) {
		long i = 2;
		long nPrime = 0;
		long sum = 0;
		while (i < n) {
			if (isPrime(i)) {
				System.out.println(i);
				nPrime = i;
				sum += nPrime;
			}
			i++;
		}
		return sum;
	}

	public static long largestProducGrid() {
		int matrix[][] = { { 8, 02, 22, 97, 38, 15, 00, 40, 00, 75, 04, 05, 07, 78, 52, 12, 50, 77, 91, 8 },
				{ 49, 49, 99, 40, 17, 81, 18, 57, 60, 87, 17, 40, 98, 43, 69, 48, 04, 56, 62, 00 },
				{ 81, 49, 31, 73, 55, 79, 14, 29, 93, 71, 40, 67, 53, 88, 30, 03, 49, 13, 36, 65 },
				{ 52, 70, 95, 23, 04, 60, 11, 42, 69, 24, 68, 56, 01, 32, 56, 71, 37, 02, 36, 91 },
				{ 22, 31, 16, 71, 51, 67, 63, 89, 41, 92, 36, 54, 22, 40, 40, 28, 66, 33, 13, 80 },
				{ 24, 47, 32, 60, 99, 03, 45, 02, 44, 75, 33, 53, 78, 36, 84, 20, 35, 17, 12, 50 },
				{ 32, 98, 81, 28, 64, 23, 67, 10, 26, 38, 40, 67, 59, 54, 70, 66, 18, 38, 64, 70 },
				{ 67, 26, 20, 68, 02, 62, 12, 20, 95, 63, 94, 39, 63, 8, 40, 91, 66, 49, 94, 21 },
				{ 24, 55, 58, 05, 66, 73, 99, 26, 97, 17, 78, 78, 96, 83, 14, 88, 34, 89, 63, 72 },
				{ 21, 36, 23, 9, 75, 00, 76, 44, 20, 45, 35, 14, 00, 61, 33, 97, 34, 31, 33, 95 },
				{ 78, 17, 53, 28, 22, 75, 31, 67, 15, 94, 03, 80, 04, 62, 16, 14, 9, 53, 56, 92 },
				{ 16, 39, 05, 42, 96, 35, 31, 47, 55, 58, 88, 24, 00, 17, 54, 24, 36, 29, 85, 57 },
				{ 86, 56, 00, 48, 35, 71, 89, 07, 05, 44, 44, 37, 44, 60, 21, 58, 51, 54, 17, 58 },
				{ 19, 80, 81, 68, 05, 94, 47, 69, 28, 73, 92, 13, 86, 52, 17, 77, 04, 89, 55, 40 },
				{ 04, 52, 8, 83, 97, 35, 99, 16, 07, 97, 57, 32, 16, 26, 26, 79, 33, 27, 98, 66 },
				{ 88, 36, 68, 87, 57, 62, 20, 72, 03, 46, 33, 67, 46, 55, 12, 32, 63, 93, 53, 69 },
				{ 04, 42, 16, 73, 38, 25, 39, 11, 24, 94, 72, 18, 8, 46, 29, 32, 40, 62, 76, 36 },
				{ 20, 69, 36, 41, 72, 30, 23, 88, 34, 62, 99, 69, 82, 67, 59, 85, 74, 04, 36, 16 },
				{ 20, 73, 35, 29, 78, 31, 90, 01, 74, 31, 49, 71, 48, 86, 81, 16, 23, 57, 05, 54 },
				{ 01, 70, 54, 71, 83, 51, 54, 69, 16, 92, 33, 48, 61, 43, 52, 01, 89, 19, 67, 48 } };

		long max = 0;

		for (int i = 0; i < 20; i++) {
			for (int j = 0; j < 20; j++) {
				long up = 0;
				long down = 0;
				long left = 0;
				long right = 0;
				long northEast = 0;
				long northWest = 0;
				long southEast = 0;
				long southWest = 0;
				if (i - 3 >= 0) {
					up = matrix[i][j] * matrix[i - 1][j] * matrix[i - 2][j] * matrix[i - 3][j];
				}
				if (i + 3 < matrix.length) {
					down = matrix[i][j] * matrix[i + 1][j] * matrix[i + 2][j] * matrix[i + 3][j];
				}
				if (j - 3 >= 0) {
					left = matrix[i][j] * matrix[i][j - 1] * matrix[i][j - 2] * matrix[i][j - 3];
				}
				if (j + 3 < matrix[j].length) {
					right = matrix[i][j] * matrix[i][j + 1] * matrix[i][j + 2] * matrix[i][j + 3];
				}
				if (i - 3 >= 0 && j - 3 >= 0) {
					northWest = matrix[i][j] * matrix[i - 1][j - 1] * matrix[i - 2][j - 2] * matrix[i - 3][j - 3];
				}
				if (i - 3 >= 0 && j + 3 < matrix[j].length) {
					northEast = matrix[i][j] * matrix[i - 1][j + 1] * matrix[i - 2][j + 2] * matrix[i - 3][j + 3];
				}
				if (i + 3 < matrix.length && j - 3 >= 0) {
					southEast = matrix[i][j] * matrix[i + 1][j - 1] * matrix[i + 2][j - 2] * matrix[i + 3][j - 3];

				}
				if (i + 3 < matrix.length && j + 3 < matrix[j].length) {
					southWest = matrix[i][j] * matrix[i + 1][j + 1] * matrix[i + 2][j + 2] * matrix[i + 3][j + 3];
				}
				if (up > max) {
					max = up;
				}
				if (down > max) {
					max = down;
				}
				if (right > max) {
					max = right;
				}
				if (left > max) {
					max = left;
				}
				if (northEast > max) {
					max = northEast;
				}
				if (northWest > max) {
					max = northWest;
				}
				if (southEast > max) {
					max = southEast;
				}
				if (southWest > max) {
					max = southWest;
				}
			}
		}
		return max;
	}

	public static String sumBigNumber() {
		String bigNumbers[] = { "37107287533902102798797998220837590246510135740250",
				"46376937677490009712648124896970078050417018260538",
				"74324986199524741059474233309513058123726617309629",
				"91942213363574161572522430563301811072406154908250",
				"23067588207539346171171980310421047513778063246676",
				"89261670696623633820136378418383684178734361726757",
				"28112879812849979408065481931592621691275889832738",
				"44274228917432520321923589422876796487670272189318",
				"47451445736001306439091167216856844588711603153276",
				"70386486105843025439939619828917593665686757934951",
				"62176457141856560629502157223196586755079324193331",
				"64906352462741904929101432445813822663347944758178",
				"92575867718337217661963751590579239728245598838407",
				"58203565325359399008402633568948830189458628227828",
				"80181199384826282014278194139940567587151170094390",
				"35398664372827112653829987240784473053190104293586",
				"86515506006295864861532075273371959191420517255829",
				"71693888707715466499115593487603532921714970056938",
				"54370070576826684624621495650076471787294438377604",
				"53282654108756828443191190634694037855217779295145",
				"36123272525000296071075082563815656710885258350721",
				"45876576172410976447339110607218265236877223636045",
				"17423706905851860660448207621209813287860733969412",
				"81142660418086830619328460811191061556940512689692",
				"51934325451728388641918047049293215058642563049483",
				"62467221648435076201727918039944693004732956340691",
				"15732444386908125794514089057706229429197107928209",
				"55037687525678773091862540744969844508330393682126",
				"18336384825330154686196124348767681297534375946515",
				"80386287592878490201521685554828717201219257766954",
				"78182833757993103614740356856449095527097864797581",
				"16726320100436897842553539920931837441497806860984",
				"48403098129077791799088218795327364475675590848030",
				"87086987551392711854517078544161852424320693150332",
				"59959406895756536782107074926966537676326235447210",
				"69793950679652694742597709739166693763042633987085",
				"41052684708299085211399427365734116182760315001271",
				"65378607361501080857009149939512557028198746004375",
				"35829035317434717326932123578154982629742552737307",
				"94953759765105305946966067683156574377167401875275",
				"88902802571733229619176668713819931811048770190271",
				"25267680276078003013678680992525463401061632866526",
				"36270218540497705585629946580636237993140746255962",
				"24074486908231174977792365466257246923322810917141",
				"91430288197103288597806669760892938638285025333403",
				"34413065578016127815921815005561868836468420090470",
				"23053081172816430487623791969842487255036638784583",
				"11487696932154902810424020138335124462181441773470",
				"63783299490636259666498587618221225225512486764533",
				"67720186971698544312419572409913959008952310058822",
				"95548255300263520781532296796249481641953868218774",
				"76085327132285723110424803456124867697064507995236",
				"37774242535411291684276865538926205024910326572967",
				"23701913275725675285653248258265463092207058596522",
				"29798860272258331913126375147341994889534765745501",
				"18495701454879288984856827726077713721403798879715",
				"38298203783031473527721580348144513491373226651381",
				"34829543829199918180278916522431027392251122869539",
				"40957953066405232632538044100059654939159879593635",
				"29746152185502371307642255121183693803580388584903",
				"41698116222072977186158236678424689157993532961922",
				"62467957194401269043877107275048102390895523597457",
				"23189706772547915061505504953922979530901129967519",
				"86188088225875314529584099251203829009407770775672",
				"11306739708304724483816533873502340845647058077308",
				"82959174767140363198008187129011875491310547126581",
				"97623331044818386269515456334926366572897563400500",
				"42846280183517070527831839425882145521227251250327",
				"55121603546981200581762165212827652751691296897789",
				"32238195734329339946437501907836945765883352399886",
				"75506164965184775180738168837861091527357929701337",
				"62177842752192623401942399639168044983993173312731",
				"32924185707147349566916674687634660915035914677504",
				"99518671430235219628894890102423325116913619626622",
				"73267460800591547471830798392868535206946944540724",
				"76841822524674417161514036427982273348055556214818",
				"97142617910342598647204516893989422179826088076852",
				"87783646182799346313767754307809363333018982642090",
				"10848802521674670883215120185883543223812876952786",
				"71329612474782464538636993009049310363619763878039",
				"62184073572399794223406235393808339651327408011116",
				"66627891981488087797941876876144230030984490851411",
				"60661826293682836764744779239180335110989069790714",
				"85786944089552990653640447425576083659976645795096",
				"66024396409905389607120198219976047599490197230297",
				"64913982680032973156037120041377903785566085089252",
				"16730939319872750275468906903707539413042652315011",
				"94809377245048795150954100921645863754710598436791",
				"78639167021187492431995700641917969777599028300699",
				"15368713711936614952811305876380278410754449733078",
				"40789923115535562561142322423255033685442488917353",
				"44889911501440648020369068063960672322193204149535",
				"41503128880339536053299340368006977710650566631954",
				"81234880673210146739058568557934581403627822703280",
				"82616570773948327592232845941706525094512325230608",
				"22918802058777319719839450180888072429661980811197",
				"77158542502016545090413245809786882778948721859617",
				"72107838435069186155435662884062257473692284509516",
				"20849603980134001723930671666823555245252804609722",
				"53503534226472524250874054075591789781264330331690" };

		BigDecimal sum = BigDecimal.ZERO;
		for (int i = 0; i < bigNumbers.length; i++) {
			sum = sum.add(new BigDecimal(bigNumbers[i]));
		}
		return sum.toPlainString().substring(0, 10);
	}

	public static long powerDigitSum(int x, int power) {
		BigDecimal bigNumber = new BigDecimal(Math.pow(x, power));
		String numberToParse = String.valueOf(bigNumber);
		int sum = 0;
		for (int i = 0; i < numberToParse.length(); i++) {
			sum += Character.getNumericValue(numberToParse.charAt(i));
		}
		return sum;
	}

	public static int fibonacciIndex() {
		BigDecimal a = BigDecimal.ZERO;
		BigDecimal b = BigDecimal.ONE;
		int count = 0;

		while (a.toPlainString().length() != 1000) {
			a = a.add(b);
			b = a.subtract(b);
			count++;
			System.out.println(a);
		}
		return count;
	}

	public static long longestCollatzSequence() {
		long max = 0;
		for (int i = 1; i < 1000000; i++) {
			int n = i;
			long count = 0;
			while (n != 1) {
				if (n % 2 == 0) {
					n = n / 2;
				} else {
					n = 3 * n + 1;
				}
				System.out.println(count);
				count++;
			}
			if (count > max) {
				max = count;
			}
		}
		return max;
	}

	public static long triangularNumbers() {
		int countDivisors = 0;
		long n = 0;
		long i = 0;
		while (countDivisors <= 500) {
			n += i;
			countDivisors = getTotalDivisors(n);
			System.out.println(n + " = " + countDivisors);
			i++;
		}
		return n;
	}

	public static int getTotalDivisors(long n) {
		long limit = n;
		int numberOfDivisors = 0;

		if (n == 1)
			return 1;

		for (long i = 1; i < limit; i++) {
			if (n % i == 0) {
				limit = n / i;
				if (limit != i) {
					numberOfDivisors++;
				}
				numberOfDivisors++;
			}
		}

		return numberOfDivisors;
	}

	public static List<Long> getDivisorsList(long n) {
		List<Long> divisors = new ArrayList<Long>();
		for (long i = 1; i <= Math.sqrt(n); i++) {
			if (n % i == 0) {
				divisors.add(i);
				if (i != Math.sqrt(n)) {
					divisors.add(n / i);
				}
			}
		}
		return divisors;
	}

	public static String factorToString(int n) {
		BigDecimal total = new BigDecimal(n);
		for (int i = n - 1; i > 0; i--) {
			total = total.multiply(new BigDecimal(i));
		}
		return total.toPlainString();
	}

	public static int sumOfFactors(int n) {
		String bigNumber = factorToString(n);
		int total = 0;
		for (int i = 0; i < bigNumber.length(); i++) {
			total += Character.getNumericValue(bigNumber.charAt(i));
		}
		return total;
	}

	public static String routesGrid(int n, int k) {
		BigDecimal result = new BigDecimal(1);

		for (long i = n; i > n - k; i--) {
			result = result.multiply(new BigDecimal(i));
		}

		for (long i = k; i > 1; i--) {
			result = result.divide(new BigDecimal(i));
		}
		return result.toPlainString();
	}

}