move dmath, dsafe and nixctor to snippets/ directory

snippets/dmath/hcf.d

@@ -0,0 +1,36 @@
+import std.conv : to;
+import std.stdio : write, writeln;
+
+void
+main(string[] args)
+{
+	int i, x, y;
+	int[] xf, yf;
+
+	x = args[1].to!int();
+	y = args[2].to!int();
+
+	xf = factorsOf(x);
+	yf = factorsOf(y);
+	for (i = 0; xf.length > i || yf.length > i; i++) {
+		if (i < xf.length)
+			write(xf[i]);
+		write("	");
+		if (i < yf.length)
+			write(yf[i]);
+		writeln();
+	}
+}
+
+int[]
+factorsOf(int x)
+{
+	int[] a;
+
+	foreach (int i; 1 .. x + 1) {
+		if (x % i == 0)
+			a ~= i;
+	}
+
+	return a;
+}