C++程序  |  90行  |  2.76 KB

//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// <valarray>

// template<class T> class valarray;

// void swap(valarray& v);

#include <valarray>
#include <cassert>

int main()
{
    {
        typedef int T;
        T a1[] = {1, 2, 3, 4, 5};
        T a2[] = {6, 7, 8, 9, 10, 11, 12};
        const unsigned N1 = sizeof(a1)/sizeof(a1[0]);
        const unsigned N2 = sizeof(a2)/sizeof(a2[0]);
        std::valarray<T> v1(a1, N1);
        std::valarray<T> v2(a2, N2);
        std::valarray<T> v1_save = v1;
        std::valarray<T> v2_save = v2;
        v1.swap(v2);
        assert(v1.size() == v2_save.size());
        for (int i = 0; i < v1.size(); ++i)
            assert(v1[i] == v2_save[i]);
        assert(v2.size() == v1_save.size());
        for (int i = 0; i < v2.size(); ++i)
            assert(v2[i] == v1_save[i]);
    }
    {
        typedef int T;
        T a1[] = {1, 2, 3, 4, 5};
        const unsigned N1 = sizeof(a1)/sizeof(a1[0]);
        const unsigned N2 = 0;
        std::valarray<T> v1(a1, N1);
        std::valarray<T> v2;
        std::valarray<T> v1_save = v1;
        std::valarray<T> v2_save = v2;
        v1.swap(v2);
        assert(v1.size() == v2_save.size());
        for (int i = 0; i < v1.size(); ++i)
            assert(v1[i] == v2_save[i]);
        assert(v2.size() == v1_save.size());
        for (int i = 0; i < v2.size(); ++i)
            assert(v2[i] == v1_save[i]);
    }
    {
        typedef int T;
        T a2[] = {6, 7, 8, 9, 10, 11, 12};
        const unsigned N1 = 0;
        const unsigned N2 = sizeof(a2)/sizeof(a2[0]);
        std::valarray<T> v1;
        std::valarray<T> v2(a2, N2);
        std::valarray<T> v1_save = v1;
        std::valarray<T> v2_save = v2;
        v1.swap(v2);
        assert(v1.size() == v2_save.size());
        for (int i = 0; i < v1.size(); ++i)
            assert(v1[i] == v2_save[i]);
        assert(v2.size() == v1_save.size());
        for (int i = 0; i < v2.size(); ++i)
            assert(v2[i] == v1_save[i]);
    }
    {
        typedef int T;
        const unsigned N1 = 0;
        const unsigned N2 = 0;
        std::valarray<T> v1;
        std::valarray<T> v2;
        std::valarray<T> v1_save = v1;
        std::valarray<T> v2_save = v2;
        v1.swap(v2);
        assert(v1.size() == v2_save.size());
        for (int i = 0; i < v1.size(); ++i)
            assert(v1[i] == v2_save[i]);
        assert(v2.size() == v1_save.size());
        for (int i = 0; i < v2.size(); ++i)
            assert(v2[i] == v1_save[i]);
    }
}