Add more CTL content

ctl/partition.h

@@ -0,0 +1,29 @@
+// -*-mode:c++;indent-tabs-mode:nil;c-basic-offset:4;tab-width:8;coding:utf-8-*-
+// vi: set et ft=cpp ts=4 sts=4 sw=4 fenc=utf-8 :vi
+#ifndef CTL_PARTITION_H_
+#define CTL_PARTITION_H_
+#include "utility.h"
+
+namespace ctl {
+
+template<typename RandomIt, typename Compare>
+RandomIt
+partition(RandomIt first, RandomIt last, Compare comp)
+{
+    auto pivot = *ctl::move(last - 1);
+    auto i = first - 1;
+
+    for (auto j = first; j < last - 1; ++j) {
+        if (comp(*j, pivot)) {
+            ++i;
+            ctl::swap(*i, *j);
+        }
+    }
+
+    ctl::swap(*(i + 1), *(last - 1));
+    return i + 1;
+}
+
+} // namespace ctl
+
+#endif // CTL_PARTITION_H_