Added last 2 functions

assignment/pyramid_of_numbers.c

@@ -1,9 +1,9 @@
 /*----------------------------------------------------------
- *				HTBLA-Leonding / Class: <your class>
+ *				HTBLA-Leonding / Class: 2IHIF
  * ---------------------------------------------------------
  * Exercise Number: 0
  * Title:			Pyramid of Numbers
- * Author:			<your name>
+ * Author:			Marc Tismonar
  * ----------------------------------------------------------
  * Description:
  * Calculates a pyramid of numbers, i.e., it multiplies a big
@@ -13,6 +13,7 @@
  * ----------------------------------------------------------
  */
 #include <stdio.h>
+#include <string.h>
 
 /// The maximum number of digits allowed in a big int.
 #define MAX_DIGITS 80
@@ -36,32 +37,99 @@ struct BigInt {
 *** @param *big_int The converted string now as BigInt.
 * @return The number of characters converted.
 */
-int strtobig_int(const char* str, int len, struct BigInt* big_int);
+int strtobig_int(const char* str, int len, struct BigInt* big_int) {
+	int conversions = 0;
+	for (int i = 0; i < len; i++)
+	{
+		int converted = str[i] - '0';
+		if (converted >= 0 && converted <= 9)
+		{
+			big_int->the_int[conversions] = converted;
+			conversions++;
+		}
+		else
+		{
+			big_int->digits_count = conversions;
+			return conversions;
+		}
+	}
+	big_int->digits_count = conversions;
+	return conversions;
+}
 
 /** print_big_int() prints a BigInt.
 *** @param *big_int The BigInt to be printed.
 */
-void print_big_int(const struct BigInt *big_int);
+void print_big_int(const struct BigInt *big_int) {
+	for (int i = 0; i < big_int->digits_count; i++)
+	{
+		printf("%d", big_int->the_int[i]);
+	}
+}
 
 /** multiply() multiplies a BigInt by an int.
 *** @param big_int The BigInt to be multiplied.
 *** @param factor The int value which is multiplied by BigInt.
 *** @param *big_result The result of the multiplication.
 */
-void multiply(const struct BigInt* big_int, int factor, struct BigInt* big_result);
+void multiply(const struct BigInt* big_int, int factor, struct BigInt* big_result) {
+	int overflow = 0;
+	int sizeOfResult = big_int->digits_count + 1;
+	char big_str_result[sizeOfResult];
+	for(int i = 0; i < big_int->digits_count; i++)
+	{
+		int result = big_int->the_int[i] * factor + overflow;
+		if (result > 9)
+		{
+			overflow = result / 10;
+			result = result - overflow;
+		}
+		big_str_result[i] = result + '0';
+	}
+	if (big_str_result[sizeOfResult - 1] == '0')
+	{
+		sizeOfResult--;
+	}
+
+	strtobig_int(big_str_result, sizeOfResult, big_result);
+}
 
 /** divide() multiplies a BigInt by an int.
 *** @param big_int The BigInt to be divided.
 *** @param divisor The int value by which we want to devide big_int.
 *** @param *big_result The result of the division.
 */
-void divide(const struct BigInt* big_int, int divisor, struct BigInt* big_result);
+void divide(const struct BigInt* big_int, int divisor, struct BigInt* big_result) {
+	int remainder = 0;
+	int sizeOfResult = big_int->digits_count;
+	char str_result[sizeOfResult];
+	for (int i = 0; i < big_int->digits_count; i++)
+	{
+		int calculate = remainder * 10;
+		calculate += big_int->the_int[i];
+		int result = calculate / divisor;
+		if (result == 0) {
+			remainder = big_int->the_int[i];
+		}
+		str_result[i] = result + '0';
+	}
+	if (str_result[sizeOfResult - 1] == '0')
+	{
+		sizeOfResult--;
+	}
+	strtobig_int(str_result, sizeOfResult, big_result);
+}
 
 /** copy_big_int() copies a BigInt to another BigInt.
 *** @param from The source where we want to copy from.
 *** @param *to The target where we want to copy to.
 */
-void copy_big_int(const struct BigInt* from, struct BigInt* to);
+void copy_big_int(const struct BigInt* from, struct BigInt* to) {
+	to->digits_count = from->digits_count;
+	for (int i = 0; i < from->digits_count; i++) {
+		to->the_int[i] = from->the_int[i];
+	}
+}
 
 /**
 *** main() reads the base number from which the pyramid has to be calculated
@@ -76,5 +144,48 @@ void copy_big_int(const struct BigInt* from, struct BigInt* to);
 */
 int main(int argc, char* argv[])
 {
+	printf("Pyramid of Numbers\n\n");
+
+	printf("Please enter a number: ");
+	char input_str[MAX_DIGITS];
+	scanf("%s", input_str);
+
+	struct BigInt original_big_int;
+	int len = strlen(input_str);
+	strtobig_int(input_str, len, &original_big_int);
+
+	struct BigInt changed_big_int;
+	copy_big_int(&original_big_int, &changed_big_int);
+
+	//multiply
+	for (int i = 2; i < 10; i++)
+	{
+		//create temp BigInt & multiply
+		struct BigInt temp;
+		multiply(&changed_big_int, i, &temp);
+		
+		print_big_int(&changed_big_int);
+		printf(" * %d = ", i);
+		print_big_int(&temp);
+		printf("\n");
+
+		copy_big_int(&temp, &changed_big_int);
+	}
+
+	//divide
+	for (int i = 9; i > 1; i--)
+	{
+		//create temp BigInt & multiply
+		struct BigInt temp;
+		divide(&changed_big_int, i, &temp);
+		
+		print_big_int(&changed_big_int);
+		printf(" / %d = ", i);
+		print_big_int(&temp);
+		printf("\n");
+
+		copy_big_int(&temp, &changed_big_int);
+	}
+
 	return 0;
 }