本文整理汇总了C++中ranges::begin方法的典型用法代码示例。如果您正苦于以下问题：C++ ranges::begin方法的具体用法？C++ ranges::begin怎么用？C++ ranges::begin使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类ranges的用法示例。
在下文中一共展示了ranges::begin方法的4个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: main
int main()
{
using ranges::begin;
using ranges::end;
using ranges::size;
std::pair<int, int> const a[] = {{0, 0}, {0, 1}, {1, 2}, {1, 3}, {3, 4}, {3, 5}};
static_assert(size(a) == 6, "");
std::pair<int, int> out[size(a)] = {};
auto res = ranges::copy_backward(begin(a), end(a), end(out));
CHECK(res.first == end(a));
CHECK(res.second == begin(out));
CHECK(std::equal(a, a + size(a), out));
std::fill_n(out, size(out), std::make_pair(0, 0));
CHECK(!std::equal(a, a + size(a), out));
res = ranges::copy_backward(a, end(out));
CHECK(res.first == end(a));
CHECK(res.second == begin(out));
CHECK(std::equal(a, a + size(a), out));
std::fill_n(out, size(out), std::make_pair(0, 0));
auto res2 = ranges::copy_backward(ranges::move(a), end(out));
CHECK(res2.first.get_unsafe() == end(a));
CHECK(res2.second == begin(out));
CHECK(std::equal(a, a + size(a), out));
test_repeat_view();
test_initializer_list();
return test_result();
}示例2: main
int main()
{
using ranges::begin;
using ranges::end;
using ranges::size;
std::pair<int, int> const a[] = {{0, 0}, {0, 1}, {1, 2}, {1, 3}, {3, 4}, {3, 5}};
static_assert(size(a) == 6, "");
std::pair<int, int> out[size(a)] = {};
auto res = ranges::copy(begin(a), end(a), out);
CHECK(res.first == end(a));
CHECK(res.second == out + size(out));
CHECK(&res.first == &res.in());
CHECK(&res.second == &res.out());
CHECK(std::equal(a, a + size(a), out));
std::fill_n(out, size(out), std::make_pair(0, 0));
CHECK(!std::equal(a, a + size(a), out));
res = ranges::copy(a, out);
CHECK(res.first == a + size(a));
CHECK(res.second == out + size(out));
CHECK(std::equal(a, a + size(a), out));
std::fill_n(out, size(out), std::make_pair(0, 0));
using ranges::view::delimit;
{
char const *sz = "hello world";
char buf[50];
auto str = delimit(sz, '\0');
auto res3 = ranges::copy(str, buf);
*res3.second = '\0';
CHECK(res3.first == std::next(begin(str), static_cast<std::ptrdiff_t>(std::strlen(sz))));
CHECK(res3.second == buf + std::strlen(sz));
CHECK(std::strcmp(sz, buf) == 0);
}
{
char const *sz = "hello world";
char buf[50];
auto str = delimit(sz, '\0');
auto res3 = ranges::copy(std::move(str), buf);
*res3.second = '\0';
CHECK(res3.first.get_unsafe() == std::next(begin(str), static_cast<std::ptrdiff_t>(std::strlen(sz))));
CHECK(res3.second == buf + std::strlen(sz));
CHECK(std::strcmp(sz, buf) == 0);
}
return test_result();
}示例3: nextrange
//intersect(currentHint,possibleRanges[j])
//modifies rangelist
range nextrange(ranges &rangelist, range &myrange)
{
if(rangelist.empty())
{
range retRange = myrange;
myrange.start = myrange.end+1;
return retRange;
}
else
{
if(myrange.start > rangelist[0].end)
{
//rangelist[0] is the next range for sure.
range retRange = rangelist[0];
rangelist.erase(rangelist.begin());
return retRange;
}
else if(myrange.start == rangelist[0].end)
{
if(rangelist[0].start == rangelist[0].end )
{
rangelist[0].score++;
range retRange = rangelist[0];
rangelist.erase(rangelist.begin());
myrange.start++;
return retRange;
}
else
{
range retRange = rangelist[0];
retRange.end--;
rangelist[0].start = rangelist[0].end;
rangelist[0].score++;
myrange.start++;
return retRange;
}
}
else if(myrange.start >rangelist[0].start)
{
//we have an intersection here. rangelist[0] <=> myrange.start-1
//update rangelist first element accordingly
range retRange = range(rangelist[0].start,myrange.start-1,rangelist[0].score);
rangelist[0].start = myrange.start;
return retRange;
}
else if(myrange.start == rangelist[0].start)
{
if(myrange.end < rangelist[0].end)
{
// myrange.start to myrange.end is the next range.
// We add 1 to score of rangelist[0] score
range retRange = range(myrange.start,myrange.end,rangelist[0].score+1);
rangelist[0].start = myrange.end+1;
myrange.start = myrange.end+1;
return retRange;
}
else
{
//takes care of myrange.end = rl[0].end also
// rangelist[0] with inc score is the nextrange. Remove it from the list.
// update myrange accordingly
range retRange = range(rangelist[0].start,rangelist[0].end,rangelist[0].score+1);
myrange.start = rangelist[0].end+1;
rangelist.erase(rangelist.begin());
return retRange;
}
}
else
{
//myrange.start < rangelist[0].start
int end = MIN(myrange.end,rangelist[0].start-1);
range retRange = range(myrange.start,end,1);
myrange.start = end+1;
return retRange;
}
}
}示例4: main
int main()
{
using ranges::begin;
using ranges::end;
using ranges::size;
using ranges::less;
using P = std::pair<int, int>;
P a[] = {{0, 0}, {0, 1}, {1, 2}, {1, 3}, {3, 4}, {3, 5}};
P const c[] = {{0, 0}, {0, 1}, {1, 2}, {1, 3}, {3, 4}, {3, 5}};
CHECK(ranges::aux::upper_bound_n(begin(a), size(a), a[0]) == &a[1]);
CHECK(ranges::aux::upper_bound_n(begin(a), size(a), a[1], less()) == &a[2]);
CHECK(ranges::aux::upper_bound_n(begin(a), size(a), 1, less(), &std::pair<int, int>::first) == &a[4]);
CHECK(ranges::upper_bound(begin(a), end(a), a[0]) == &a[1]);
CHECK(ranges::upper_bound(begin(a), end(a), a[1], less()) == &a[2]);
CHECK(ranges::upper_bound(begin(a), end(a), 1, less(), &std::pair<int, int>::first) == &a[4]);
CHECK(ranges::upper_bound(a, a[2]) == &a[3]);
CHECK(ranges::upper_bound(c, c[3]) == &c[4]);
CHECK(ranges::upper_bound(a, a[4], less()) == &a[5]);
CHECK(ranges::upper_bound(c, c[5], less()) == &c[6]);
CHECK(ranges::upper_bound(a, 1, less(), &std::pair<int, int>::first) == &a[4]);
CHECK(ranges::upper_bound(c, 1, less(), &std::pair<int, int>::first) == &c[4]);
std::vector<P> vec_a(ranges::begin(a), ranges::end(a));
std::vector<P> const vec_c(ranges::begin(c), ranges::end(c));
CHECK(ranges::upper_bound(ranges::view::all(a), a[2]) == &a[3]);
CHECK(ranges::upper_bound(ranges::view::all(c), c[3]) == &c[4]);
#ifndef RANGES_WORKAROUND_MSVC_573728
CHECK(::is_dangling(ranges::upper_bound(std::move(a), a[2])));
CHECK(::is_dangling(ranges::upper_bound(std::move(c), c[3])));
#endif // RANGES_WORKAROUND_MSVC_573728
CHECK(::is_dangling(ranges::upper_bound(std::move(vec_a), vec_a[2])));
CHECK(::is_dangling(ranges::upper_bound(std::move(vec_c), vec_c[3])));
CHECK(ranges::upper_bound(ranges::view::all(a), a[4], less()) == &a[5]);
CHECK(ranges::upper_bound(ranges::view::all(c), c[5], less()) == &c[6]);
#ifndef RANGES_WORKAROUND_MSVC_573728
CHECK(::is_dangling(ranges::upper_bound(std::move(a), a[4], less())));
CHECK(::is_dangling(ranges::upper_bound(std::move(c), c[5], less())));
#endif // RANGES_WORKAROUND_MSVC_573728
CHECK(::is_dangling(ranges::upper_bound(std::move(vec_a), vec_a[4], less())));
CHECK(::is_dangling(ranges::upper_bound(std::move(vec_c), vec_c[5], less())));
CHECK(ranges::upper_bound(ranges::view::all(a), 1, less(), &std::pair<int, int>::first) == &a[4]);
CHECK(ranges::upper_bound(ranges::view::all(c), 1, less(), &std::pair<int, int>::first) == &c[4]);
#ifndef RANGES_WORKAROUND_MSVC_573728
CHECK(::is_dangling(ranges::upper_bound(std::move(a), 1, less(), &std::pair<int, int>::first)));
CHECK(::is_dangling(ranges::upper_bound(std::move(c), 1, less(), &std::pair<int, int>::first)));
#endif // RANGES_WORKAROUND_MSVC_573728
CHECK(::is_dangling(ranges::upper_bound(std::move(vec_a), 1, less(), &std::pair<int, int>::first)));
CHECK(::is_dangling(ranges::upper_bound(std::move(vec_c), 1, less(), &std::pair<int, int>::first)));
return test_result();
}