1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // <random>
10 
11 // class seed_seq;
12 
13 // template<class InputIterator>
14 //     seed_seq(InputIterator begin, InputIterator end);
15 
16 #include <random>
17 #include <cassert>
18 
19 #include "test_macros.h"
20 
21 void test()
22 {
23   {
24     unsigned a[5] = {5, 4, 3, 2, 1};
25     std::seed_seq s(a, a+5);
26     assert(s.size() == 5);
27 
28     unsigned b[5] = {0};
29     s.param(b);
30     assert(b[0] == 5);
31     assert(b[1] == 4);
32     assert(b[2] == 3);
33     assert(b[3] == 2);
34     assert(b[4] == 1);
35   }
36   {
37     // Test truncation to 32 bits
38     unsigned long long a[4] = {
39       0x1234000056780000uLL,
40       0x0000001234567800uLL,
41       0xFFFFFFFFFFFFFFFFuLL,
42       0x0000000180000000uLL,
43     };
44     std::seed_seq s(a, a+4);
45     assert(s.size() == 4);
46 
47     unsigned b[4] = {0};
48     s.param(b);
49     assert(b[0] == 0x56780000u);
50     assert(b[1] == 0x34567800u);
51     assert(b[2] == 0xFFFFFFFFu);
52     assert(b[3] == 0x80000000u);
53   }
54 #if TEST_STD_VER >= 11
55   {
56     // Test uniform initialization syntax (LWG 3422)
57     unsigned a[3] = {1, 2, 3};
58     std::seed_seq s{a, a+3};  // uniform initialization
59     assert(s.size() == 3);
60 
61     unsigned b[3] = {0};
62     s.param(b);
63     assert(b[0] == 1);
64     assert(b[1] == 2);
65     assert(b[2] == 3);
66   }
67 #endif // TEST_STD_VER >= 11
68 }
69 
70 int main(int, char**)
71 {
72   test();
73 
74   return 0;
75 }
76