libcxx initial import

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@103490 91177308-0d34-0410-b5e6-96231b3b80d8

test/containers/unord/next_prime.pass.cpp

@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+// <20><><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD><EFBFBD>The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// Not a portable test
+
+// <__hash_table>
+
+// size_t __next_prime(size_t n);
+
+// If n == 0, return 0, else return the lowest prime greater than or equal to n
+
+#include <__hash_table>
+#include <cassert>
+
+bool
+is_prime(size_t n)
+{
+    switch (n)
+    {
+    case 0:
+    case 1:
+        return false;
+    }
+    for (size_t i = 2; i*i <= n; ++i)
+    {
+        if (n % i == 0)
+            return false;
+    }
+    return true;
+}
+
+int main()
+{
+    assert(std::__next_prime(0) == 0);
+    for (std::size_t n = 1; n <= 100000; ++n)
+    {
+        std::size_t p = std::__next_prime(n);
+        assert(p >= n);
+        for (std::size_t i = n; i < p; ++i)
+            assert(!is_prime(i));
+        assert(is_prime(p));
+    }
+}