//===----------------------------------------------------------------------===//
//
//                     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 mask_array

// void operator-=(const valarray<value_type>& v) const;

#include <valarray>
#include <cassert>

int main()
{
    int a1[] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15};
    const std::size_t N1 = sizeof(a1)/sizeof(a1[0]);
    int a2[] = {1, 2, 3, 4, 5};
    const std::size_t N2 = sizeof(a2)/sizeof(a2[0]);
    bool b[N1] = {true,  false, false, true,  true,  false,
                  false, true,  false, false, false, true};
    std::valarray<int> v1(a1, N1);
    std::valarray<int> v2(a2, N2);
    assert(N2 == std::count(b, b+N1, true));
    std::valarray<bool> vb(b, N1);
    v1[vb] -= v2;
    assert(v1.size() == 16);
    assert(v1[ 0] == -1);
    assert(v1[ 1] ==  1);
    assert(v1[ 2] ==  2);
    assert(v1[ 3] ==  1);
    assert(v1[ 4] ==  1);
    assert(v1[ 5] ==  5);
    assert(v1[ 6] ==  6);
    assert(v1[ 7] ==  3);
    assert(v1[ 8] ==  8);
    assert(v1[ 9] ==  9);
    assert(v1[10] == 10);
    assert(v1[11] ==  6);
    assert(v1[12] == 12);
    assert(v1[13] == 13);
    assert(v1[14] == 14);
    assert(v1[15] == 15);
}