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roman_number.h

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+/*----------------------------------------------------------
+ *				HTBLA-Leonding 
+ * ---------------------------------------------------------
+ * Author:		Marc Tismonar
+ * ----------------------------------------------------------
+ * Description:
+ * Encapsulates roman numbers and provides basic mathematical operations.
+ * ----------------------------------------------------------
+ */
+
+#ifndef ___ROMAN_NUMBER
+#define ___ROMAN_NUMBER
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+
+typedef struct RomanNumberData* RomanNumber;
+
+/**
+ * Creates a roman number from the given string.
+ * If the given string is not valid or not a valid 
+ * number, an invalid RomanNumber is provided.
+ * 
+ * @param value The roman number string.
+ * @return RomanNumber 
+ */
+RomanNumber rn_create(char* value);
+
+/**
+ * Determines whether or not the RomanNumber is valid.
+ * 
+ * @param number The number to test.
+ * @return true if the number is valid, false otherwise.
+ */
+bool rn_is_valid(RomanNumber number);
+
+/**
+ * Provides the value of the RomanNumber or a value less 
+ * than zero, if the number is not valid.
+ * 
+ * @param number The number to convert.
+ * @return The integral value of the roman number or a value 
+ * less than 0;
+ */
+int rn_get_value(RomanNumber number);
+
+/**
+ * Calculates the greatest common divisor of two roman numbers.
+ * 
+ * @param x The first number.
+ * @param y The second number.
+ * @return The result or an invalid roman number, if at least one
+ * of the given values is invalid.
+ */
+RomanNumber rn_gcd(RomanNumber x, RomanNumber y);
+
+/**
+ * Calculates the greatest common divisor of two integers.
+ * 
+ * @param x The first operand.
+ * @param y The second operand
+ * @return The result.
+ */
+int int_gcd(int x, int y);
+
+#endif