1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// <unordered_map>
11
12// template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
13//           class Alloc = allocator<pair<const Key, T>>>
14// class unordered_map
15
16// float load_factor() const
17
18#include <unordered_map>
19#include <string>
20#include <cassert>
21#include <cmath>
22#include <cfloat>
23
24#include "test_macros.h"
25#include "min_allocator.h"
26
27int main()
28{
29    {
30        typedef std::unordered_map<int, std::string> C;
31        typedef std::pair<int, std::string> P;
32        P a[] =
33        {
34            P(10, "ten"),
35            P(20, "twenty"),
36            P(30, "thirty"),
37            P(40, "forty"),
38            P(50, "fifty"),
39            P(60, "sixty"),
40            P(70, "seventy"),
41            P(80, "eighty"),
42        };
43        const C c(std::begin(a), std::end(a));
44        assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
45    }
46    {
47        typedef std::unordered_map<int, std::string> C;
48        const C c;
49        assert(c.load_factor() == 0);
50    }
51#if TEST_STD_VER >= 11
52    {
53        typedef std::unordered_map<int, std::string, std::hash<int>, std::equal_to<int>,
54                            min_allocator<std::pair<const int, std::string>>> C;
55        typedef std::pair<int, std::string> P;
56        P a[] =
57        {
58            P(10, "ten"),
59            P(20, "twenty"),
60            P(30, "thirty"),
61            P(40, "forty"),
62            P(50, "fifty"),
63            P(60, "sixty"),
64            P(70, "seventy"),
65            P(80, "eighty"),
66        };
67        const C c(std::begin(a), std::end(a));
68        assert(std::fabs(c.load_factor() - (float)c.size()/c.bucket_count()) < FLT_EPSILON);
69    }
70    {
71        typedef std::unordered_map<int, std::string, std::hash<int>, std::equal_to<int>,
72                            min_allocator<std::pair<const int, std::string>>> C;
73        const C c;
74        assert(c.load_factor() == 0);
75    }
76#endif
77}
78