Problem 33

33.c

@@ -0,0 +1,32 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int gcd (int n, int d) {
+    if (n > d)
+        return gcd (n-d, d);
+    if (n < d)
+        return gcd (n, d-n);
+    else
+        return n;
+}
+
+int main (int argc, char* argv[]) {
+    int productNumerator = 1;
+    int productDenominator = 1;
+    for (int i = 1; i <= 9; i++) {
+        for (int j = 1; j <= i; j++) {
+            for (int k = 1; k <= 9; k++) {
+                int numerator = j * 10 + i;
+                int denominator = i * 10 + k;
+                if (denominator >= numerator &&
+                    denominator != numerator && 
+                    denominator * j == numerator * k) {
+                    productNumerator *= numerator;
+                    productDenominator *= denominator;
+                }
+            }
+        }
+    }
+    int greatestCommonDivisor = gcd (productNumerator, productDenominator);
+    printf ("%d\n", productDenominator / greatestCommonDivisor);
+}