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Telegram/ThirdParty/range-v3/include/range/v3/numeric/accumulate.hpp

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+/// \file
+// Range v3 library
+//
+//  Copyright Eric Niebler 2013-present
+//
+//  Use, modification and distribution is subject to the
+//  Boost Software License, Version 1.0. (See accompanying
+//  file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//
+// Project home: https://github.com/ericniebler/range-v3
+//
+#ifndef RANGES_V3_NUMERIC_ACCUMULATE_HPP
+#define RANGES_V3_NUMERIC_ACCUMULATE_HPP
+
+#include <meta/meta.hpp>
+
+#include <range/v3/functional/arithmetic.hpp>
+#include <range/v3/functional/identity.hpp>
+#include <range/v3/functional/invoke.hpp>
+#include <range/v3/iterator/concepts.hpp>
+#include <range/v3/iterator/traits.hpp>
+#include <range/v3/range/access.hpp>
+#include <range/v3/range/concepts.hpp>
+#include <range/v3/range/traits.hpp>
+#include <range/v3/utility/static_const.hpp>
+
+#include <range/v3/detail/prologue.hpp>
+
+namespace ranges
+{
+    /// \addtogroup group-numerics
+    /// @{
+    struct accumulate_fn
+    {
+        template(typename I, typename S, typename T, typename Op = plus,
+                 typename P = identity)(
+            requires sentinel_for<S, I> AND input_iterator<I> AND
+                indirectly_binary_invocable_<Op, T *, projected<I, P>> AND
+                assignable_from<T &, indirect_result_t<Op &, T *, projected<I, P>>>)
+        T operator()(I first, S last, T init, Op op = Op{},
+                        P proj = P{}) const
+        {
+            for(; first != last; ++first)
+                init = invoke(op, init, invoke(proj, *first));
+            return init;
+        }
+
+        template(typename Rng, typename T, typename Op = plus, typename P = identity)(
+            requires input_range<Rng> AND
+                indirectly_binary_invocable_<Op, T *, projected<iterator_t<Rng>, P>> AND
+                assignable_from<
+                    T &, indirect_result_t<Op &, T *, projected<iterator_t<Rng>, P>>>)
+        T operator()(Rng && rng, T init, Op op = Op{}, P proj = P{}) const
+        {
+            return (*this)(
+                begin(rng), end(rng), std::move(init), std::move(op), std::move(proj));
+        }
+    };
+
+    RANGES_INLINE_VARIABLE(accumulate_fn, accumulate)
+    /// @}
+} // namespace ranges
+
+#include <range/v3/detail/epilogue.hpp>
+
+#endif