init p1 to p9

p3.c

@@ -0,0 +1,44 @@
+
+/*
+ * http://projecteuler.net
+ * 
+ * Projecteuler - Problem 3
+ * ------------------------
+ * 10/01/10 (binary day :D) Henrik Hautakoski
+ * 
+ * fast solution using euclidean algorithm for calculating gcd.
+ */
+
+#include <stdio.h>
+
+typedef unsigned long bint;
+
+bint gcd(bint a, bint b) {
+	
+	bint c;
+	
+	while(b != 0) {
+		c = b;
+		b = a % b;
+		a = c;
+	}
+	
+	return a;
+}
+
+int main() {
+	
+	bint i, r = 0, n = 600851475143;
+	
+	for(i=2; i <= n ; i++) {
+		
+		if((r = gcd(n, i)) == 1)
+			continue;
+		
+		n /= r;
+	}
+	
+	printf("%li\n", r);
+	
+	return 0;
+}