2 files changed, 54 insertions, 0 deletions
diff --git a/rushs/evalexpr/binary_search_ptr/bsearch.c b/rushs/evalexpr/binary_search_ptr/bsearch.c
new file mode 100644
index 0000000..bdc189c
--- /dev/null
+++ b/rushs/evalexpr/binary_search_ptr/bsearch.c
@@ -0,0 +1,38 @@
+#include "bsearch.h"
+
+#include <stddef.h>
+
+int *binary_search(int *begin, int *end, int elt)
+{
+    if (begin == end)
+    {
+        return begin;
+    }
+    if (begin > end)
+    {
+        if (elt > *begin)
+        {
+            return begin + 1;
+        }
+        return begin;
+    }
+
+    size_t m = (end - begin) / 2;
+
+    if (begin[m] == elt)
+    {
+        return begin + m;
+    }
+
+    if (begin[m] > elt)
+    {
+        return binary_search(begin, begin + m, elt);
+    }
+
+    if (m == 0)
+    {
+        m++;
+    }
+
+    return binary_search(begin + m, end, elt);
+}
diff --git a/rushs/evalexpr/binary_search_ptr/bsearch.h b/rushs/evalexpr/binary_search_ptr/bsearch.h
new file mode 100644
index 0000000..e011744
--- /dev/null
+++ b/rushs/evalexpr/binary_search_ptr/bsearch.h
@@ -0,0 +1,16 @@
+#ifndef BSEARCH_H_
+#define BSEARCH_H_
+
+/*
+** Search `elt` in the memory range of [`begin` - `end`[.
+** `begin` is a pointer to the first element.
+** `end` is a pointer **AFTER** the last element.
+** The elements in the range [`begin` - `end`[ are sorted in ascending order.
+** If the range is empty, `begin` == `end`.
+** `begin` and `end` can't be `NULL`.
+** Returns a pointer to the element if found, or a pointer to the memory
+** location where the element could be inserted to keep the array sorted.
+*/
+int *binary_search(int *begin, int *end, int elt);
+
+#endif /* !BSEARCH_H_ */