The number of nanoseconds that have elapsed since epoch (tools/now.hpp)

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• Last update: 2022-11-12 12:10:52+09:00
• Include: #include "tools/now.hpp"

long long now();

It returns the number of nanoseconds that have elapsed since epoch.

Constraints

• None

Time Complexity

• $O(1)$

License

• CC0

Author

• anqooqie

Required by

• Bell numbers (tools/bell.hpp)
• Berlekamp-Massey algorithm (tools/berlekamp_massey.hpp)
• Bernoulli numbers $B_k \pmod{P}$ for $0 \leq k \leq n$ (tools/bernoulli.hpp)
• Arbitrary precision floating-point number (tools/bigdecimal.hpp)
• Arbitrary precision integer (tools/bigint.hpp)
• Bostan-Mori algorithm (tools/bostan_mori.hpp)
• Counter clockwise function (tools/ccw.hpp)
• Chromatic number (tools/chromatic_number.hpp)
• Two-dimensional circle (tools/circle_2d.hpp)
• Convex hull (tools/convex_hull.hpp)
• Convolution (tools/convolution.hpp)
• tools/detail/geometry_2d.hpp
• tools/detail/int128_t.hpp
• tools/detail/rolling_hash.hpp
• Two-dimensional directed line segment (tools/directed_line_segment_2d.hpp)
• List all divisors (tools/divisors.hpp)
• List all divisors of a divisor of $n$ (tools/divisors_of_divisor.hpp)
• Extend std::hash (tools/extend_hash.hpp)
• Extended Lucas' theorem (tools/extended_lucas.hpp)
• Cache for $n^{-1}, n!, n!^{-1} \pmod{P}$ (tools/fact_mod_cache.hpp)
• Formal power series (tools/fps.hpp)
• Garner's algorithm for $\mathbb{Z} / M_1 \mathbb{Z}$ and $\mathbb{Z} / M_2 \mathbb{Z}$ (tools/garner2.hpp)
• Garner's algorithm for $\mathbb{Z} / M_1 \mathbb{Z}$, $\mathbb{Z} / M_2 \mathbb{Z}$ and $\mathbb{Z} / M_3 \mathbb{Z}$ (tools/garner3.hpp)
• std::greater by the argument (tools/greater_by_arg.hpp)
• std::greater by the argument (total order) (tools/greater_by_arg_total.hpp)
• Two-dimensional half line (tools/half_line_2d.hpp)
• 128-bit signed integer (tools/int128_t.hpp)
• Miller-Rabin primality test (tools/is_prime.hpp)
• Precompute $n! \pmod{P}$ for $0 \leq n < P \approx 10^9$ (tools/large_fact_mod_cache.hpp)
• std::less by the argument (tools/less_by_arg.hpp)
• std::less by the argument (total order) (tools/less_by_arg_total.hpp)
• Two-dimensional line (tools/line_2d.hpp)
• $\log_x y \pmod{M}$ (tools/log_mod.hpp)
• Matrix (tools/matrix.hpp)
• tools/matrix_mod2.hpp
• $\mathbb{Z} / (2^{61} - 1) \mathbb{Z}$ (tools/modint_for_rolling_hash.hpp)
• $\mathrm{ord}(x)$ for $x \in (\mathbb{Z}/p\mathbb{Z})^\times$ (tools/ord_mod.hpp)
• Partition function (tools/partition_function.hpp)
• Two-dimensional polygon (tools/polygon_2d.hpp)
• Polynomial (tools/polynomial.hpp)
• Polynomial interpolation (tools/polynomial_interpolation.hpp)
• Popcount (tools/popcount.hpp)
• $x^y \pmod{M}$ (tools/pow_mod.hpp)
• Pollard's rho algorithm (tools/prime_factorization.hpp)
• Primitive root (tools/primitive_root.hpp)
• $x \cdot y \pmod{M}$ (tools/prod_mod.hpp)
• Quaternion (tools/quaternion.hpp)
• Rational number (tools/rational.hpp)
• Rolling hash (tools/rolling_hash.hpp)
• Shift of sampling points of polynomial (tools/sample_point_shift.hpp)
• Power of a sparse FPS (tools/sparse_fps_pow.hpp)
• $\sqrt{x} \pmod{P}$ (tools/sqrt_mod.hpp)
• Signed Stirling numbers of the first kind (tools/stirling_1st.hpp)
• Stirling numbers of the second kind (tools/stirling_2nd.hpp)
• $x \uparrow\uparrow y \pmod{M}$ (tools/tetration_mod.hpp)
• Euler's totient function (tools/totient.hpp)
• Two-dimensional triangle (tools/triangle_2d.hpp)
• Hash of std::tuple (tools/tuple_hash.hpp)
• Twelvefold way (tools/twelvefold_way.hpp)
• 128-bit unsigned integer (tools/uint128_t.hpp)
• Commonly used utilities for competitive programming (tools/util.hpp)
• Vector (tools/vector.hpp)
• Two dimensional vector (tools/vector2.hpp)
• Three dimensional vector (tools/vector3.hpp)
• Four dimensional vector (tools/vector4.hpp)

Verified with

• tests/bell/all.test.cpp
• tests/bell/consistent.test.cpp
• tests/bell/diagonal.test.cpp
• tests/bell/fixed_n.test.cpp
• tests/berlekamp_massey.test.cpp
• tests/bernoulli.test.cpp
• tests/bigdecimal/cast_to_long_long.test.cpp
• tests/bigdecimal/divides.test.cpp
• tests/bigdecimal/hand.test.cpp
• tests/bigdecimal/minus.test.cpp
• tests/bigdecimal/multiplies.test.cpp
• tests/bigdecimal/plus.test.cpp
• tests/bigdecimal/random.test.cpp
• tests/bigdecimal/rounding.test.cpp
• tests/bigint/divides.test.cpp
• tests/bigint/minus.test.cpp
• tests/bigint/modulus.test.cpp
• tests/bigint/multiplies.test.cpp
• tests/bigint/plus.test.cpp
• tests/bit_ceil.test.cpp
• tests/bit_floor.test.cpp
• tests/bit_width.test.cpp
• tests/bostan_mori.test.cpp
• tests/ccw.test.cpp
• tests/ceil_log2.test.cpp
• tests/chromatic_number.test.cpp
• tests/circle_2d/intersection_to_circle.test.cpp
• tests/circle_2d/intersection_to_line.test.cpp
• tests/circle_2d/where/with_radius.test.cpp
• tests/circle_2d/where/without_radius.test.cpp
• tests/convex_hull.test.cpp
• tests/convolution/double.test.cpp
• tests/convolution/dynamic_mod.test.cpp
• tests/convolution/mod1000000007.test.cpp
• tests/convolution/mod998244353.test.cpp
• tests/countr_zero.test.cpp
• tests/directed_line_segment_2d/cross_point.test.cpp
• tests/directed_line_segment_2d/crosses.test.cpp
• tests/directed_line_segment_2d/intersection.test.cpp
• tests/directed_line_segment_2d/squared_distance.test.cpp
• tests/divisors.test.cpp
• tests/divisors_of_divisor.test.cpp
• tests/extend_hash.test.cpp
• tests/extended_lucas.test.cpp
• tests/fact_mod_cache.test.cpp
• tests/fastio/string.test.cpp
• tests/floor_log2.test.cpp
• tests/fps/composition.test.cpp
• tests/fps/compositional_inverse.test.cpp
• tests/fps/exp_mod998244353.test.cpp
• tests/fps/exp_other_mods.test.cpp
• tests/fps/inv_mod998244353.test.cpp
• tests/fps/inv_other_mods.test.cpp
• tests/fps/log_mod998244353.test.cpp
• tests/fps/log_other_mods.test.cpp
• tests/fps/pow_mod998244353.test.cpp
• tests/fps/pow_other_mods.test.cpp
• tests/greater_by_arg.test.cpp
• tests/greater_by_arg_total.test.cpp
• tests/has_mod.test.cpp
• tests/int128_t.test.cpp
• tests/is_integral.test.cpp
• tests/is_prime.test.cpp
• tests/is_signed.test.cpp
• tests/is_unsigned.test.cpp
• tests/large_fact_mod_cache/binomial.test.cpp
• tests/large_fact_mod_cache/fact.test.cpp
• tests/less_by_arg.test.cpp
• tests/less_by_arg_total.test.cpp
• tests/line_2d/is_parallel_to.test.cpp
• tests/line_2d/projection.test.cpp
• tests/log_mod.test.cpp
• tests/make_signed.test.cpp
• tests/make_unsigned.test.cpp
• tests/matrix/determinant.test.cpp
• tests/matrix/inv.test.cpp
• tests/matrix/multiplies.test.cpp
• tests/matrix/rank.test.cpp
• tests/matrix/solve.test.cpp
• tests/matrix/static.test.cpp
• tests/matrix_mod2/determinant.test.cpp
• tests/matrix_mod2/inv.test.cpp
• tests/matrix_mod2/multiplies.test.cpp
• tests/matrix_mod2/rank.test.cpp
• tests/matrix_mod2/solve.test.cpp
• tests/monoid.test.cpp
• tests/online_cumsum.test.cpp
• tests/ord_mod/count.test.cpp
• tests/ord_mod/query.test.cpp
• tests/partition_function/all.test.cpp
• tests/partition_function/consistent.test.cpp
• tests/partition_function/diagonal.test.cpp
• tests/pdsu.test.cpp
• tests/polygon_2d/area.test.cpp
• tests/polygon_2d/minimum_bounding_circle.test.cpp
• tests/polygon_2d/where.test.cpp
• tests/polynomial/multidimensional.test.cpp
• tests/polynomial/multipoint_evaluation.test.cpp
• tests/polynomial/multipoint_evaluation_other_mods.test.cpp
• tests/polynomial/naive_division.test.cpp
• tests/polynomial/ntt_division.test.cpp
• tests/polynomial/taylor_shift.test.cpp
• tests/polynomial_interpolation.test.cpp
• tests/polynomial_product.test.cpp
• tests/popcount.test.cpp
• tests/prim/unconnected.test.cpp
• tests/prime_factorization.test.cpp
• tests/primitive_root.test.cpp
• tests/quaternion/angle_axis.test.cpp
• tests/quaternion/dice_rotations.test.cpp
• tests/quaternion/look_rotation.test.cpp
• tests/quaternion/slerp.test.cpp
• tests/rational/minus.test.cpp
• tests/rational/multiplies.test.cpp
• tests/rational/plus.test.cpp
• tests/rational/random.test.cpp
• tests/rolling_hash.test.cpp
• tests/sample_point_shift.test.cpp
• tests/sparse_fps_pow/fraction.test.cpp
• tests/sparse_fps_pow/regular.test.cpp
• tests/sqrt_mod.test.cpp
• tests/stirling_1st/consistent.test.cpp
• tests/stirling_1st/fixed_k.test.cpp
• tests/stirling_1st/fixed_n.test.cpp
• tests/stirling_2nd/all.test.cpp
• tests/stirling_2nd/consistent.test.cpp
• tests/stirling_2nd/fixed_k.test.cpp
• tests/stirling_2nd/fixed_n.test.cpp
• tests/tetration_mod.test.cpp
• tests/totient.test.cpp
• tests/triangle_2d/circumcircle.test.cpp
• tests/triangle_2d/incircle.test.cpp
• tests/tuple_hash.test.cpp
• tests/twelvefold_way/labeled_ball_labeled_box_at_least_1.test.cpp
• tests/twelvefold_way/labeled_ball_labeled_box_at_most_1.test.cpp
• tests/twelvefold_way/labeled_ball_labeled_box_unrestricted.test.cpp
• tests/twelvefold_way/labeled_ball_unlabeled_box_at_least_1.test.cpp
• tests/twelvefold_way/labeled_ball_unlabeled_box_at_most_1.test.cpp
• tests/twelvefold_way/labeled_ball_unlabeled_box_unrestricted.test.cpp
• tests/twelvefold_way/unlabeled_ball_labeled_box_at_least_1.test.cpp
• tests/twelvefold_way/unlabeled_ball_labeled_box_at_most_1.test.cpp
• tests/twelvefold_way/unlabeled_ball_labeled_box_unrestricted.test.cpp
• tests/twelvefold_way/unlabeled_ball_unlabeled_box_at_least_1.test.cpp
• tests/twelvefold_way/unlabeled_ball_unlabeled_box_at_most_1.test.cpp
• tests/twelvefold_way/unlabeled_ball_unlabeled_box_unrestricted.test.cpp
• tests/uint128_t.test.cpp
• tests/util.test.cpp
• tests/weighted_bipartite_matching/maximize.test.cpp

Code

#ifndef TOOLS_NOW_HPP
#define TOOLS_NOW_HPP

#include <chrono>

namespace tools {
  inline long long now() {
    return ::std::chrono::duration_cast<::std::chrono::nanoseconds>(::std::chrono::high_resolution_clock::now().time_since_epoch()).count();
  }
}

#endif

#line 1 "tools/now.hpp"



#include <chrono>

namespace tools {
  inline long long now() {
    return ::std::chrono::duration_cast<::std::chrono::nanoseconds>(::std::chrono::high_resolution_clock::now().time_since_epoch()).count();
  }
}

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