1// Copyright (C) 2001 Free Software Foundation, Inc. 2// 3// This file is part of the GNU ISO C++ Library. This library is free 4// software; you can redistribute it and/or modify it under the 5// terms of the GNU General Public License as published by the 6// Free Software Foundation; either version 2, or (at your option) 7// any later version. 8 9// This library is distributed in the hope that it will be useful, 10// but WITHOUT ANY WARRANTY; without even the implied warranty of 11// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12// GNU General Public License for more details. 13 14// You should have received a copy of the GNU General Public License along 15// with this library; see the file COPYING. If not, write to the Free 16// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, 17// USA. 18 19// 25.3.1 algorithms, sort() 20 21#include <algorithm> 22#include <testsuite_hooks.h> 23 24bool test __attribute__((unused)) = true; 25 26const int A[] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20}; 27const int B[] = {10, 20, 1, 11, 2, 12, 3, 13, 4, 14, 5, 15, 6, 16, 7, 17, 8, 18, 9, 19}; 28const int C[] = {20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1}; 29const int N = sizeof(A) / sizeof(int); 30const int logN = 3; // ln(N) rounded up 31const int P = 7; 32 33// comparison predicate for stable_sort: order by rightmost digit 34struct CompLast 35{ 36 bool 37 operator()(const int x, const int y) 38 { return x % 10 < y % 10; } 39}; 40 41// This functor has the equivalent functionality of std::geater<>, 42// but there is no dependency on <functional> and it also tracks the 43// number of invocations since creation. 44class Gt 45{ 46public: 47 static int count() { return itsCount; } 48 static void reset() { itsCount = 0; } 49 50 bool 51 operator()(const int& x, const int& y) 52 { 53 ++itsCount; 54 return x > y; 55 } 56 57private: 58 static int itsCount; 59}; 60 61int Gt::itsCount = 0; 62 63 64// 25.3.1.1 sort() 65void 66test01() 67{ 68 int s1[N]; 69 std::copy(B, B + N, s1); 70 VERIFY(std::equal(s1, s1 + N, B)); 71 72 std::sort(s1, s1 + N); 73 VERIFY(std::equal(s1, s1 + N, A)); 74 75 Gt gt; 76 gt.reset(); 77 std::sort(s1, s1 + N, gt); 78 VERIFY(std::equal(s1, s1 + N, C)); 79} 80 81// 25.3.1.2 stable_sort() 82void 83test02() 84{ 85 int s1[N]; 86 std::copy(A, A + N, s1); 87 VERIFY(std::equal(s1, s1 + N, A)); 88 89 std::stable_sort(s1, s1 + N, CompLast()); 90 VERIFY(std::equal(s1, s1 + N, B)); 91 92 std::stable_sort(s1, s1 + N); 93 VERIFY(std::equal(s1, s1 + N, A)); 94 95 Gt gt; 96 gt.reset(); 97 std::stable_sort(s1, s1 + N, gt); 98 VERIFY(std::equal(s1, s1 + N, C)); 99 VERIFY(gt.count() <= N * logN * logN); 100} 101 102// 25.3.1.3 partial_sort() 103void 104test03() 105{ 106 int s1[N]; 107 std::copy(B, B + N, s1); 108 VERIFY(std::equal(s1, s1 + N, B)); 109 110 std::partial_sort(s1, s1 + P, s1 + N); 111 VERIFY(std::equal(s1, s1 + P, A)); 112 113 Gt gt; 114 gt.reset(); 115 std::partial_sort(s1, s1 + P, s1 + N, gt); 116 VERIFY(std::equal(s1, s1 + P, C)); 117} 118 119// 25.3.1.4 partial_sort_copy() 120void 121test04() 122{ 123 using std::partial_sort_copy; 124 125 int s1[N]; 126 std::copy(B, B + N, s1); 127 VERIFY(std::equal(s1, s1 + N, B)); 128 129 int s2[2*N]; 130 131 partial_sort_copy(s1, s1 + N, s2, s2 + P); 132 VERIFY(std::equal(s2, s2 + P, A)); 133 134 Gt gt; 135 gt.reset(); 136 partial_sort_copy(s1, s1 + N, s2, s2 + P, gt); 137 VERIFY(std::equal(s2, s2 + P, C)); 138 139 VERIFY(std::equal(s2, partial_sort_copy(s1, s1 + N, s2, s2 + 2*N), A)); 140} 141 142// 25.3.2 nth_element() 143void 144test05() 145{ 146 using std::nth_element; 147 148 int s1[N]; 149 std::copy(B, B + N, s1); 150 VERIFY(std::equal(s1, s1 + N, B)); 151 152 int* pn = s1 + (N / 2) - 1; 153 nth_element(s1, pn, s1 + N); 154 for (const int* i = pn; i < s1 + N; ++i) VERIFY(!(*i < *pn)); 155 156 CompLast pred; 157 nth_element(s1, pn, s1 + N, pred); 158 for (const int* i = pn; i < s1 + N; ++i) VERIFY(!pred(*i, *pn)); 159} 160 161int 162main() 163{ 164 test01(); 165 test02(); 166 test03(); 167 test04(); 168 test05(); 169 170 return 0; 171} 172