std::chrono::high_resolution_clock::now

 

C++

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rel_ops::operator!=rel_ops::operator>rel_ops::operator<=rel_ops::operator>=

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Date and time utilities

time_point (C++11)

duration (C++11)

system_clock (C++11)

steady_clock (C++11)

high_resolution_clock (C++11)

C-style date and time

 

std::chrono::high_resolution_clock

Member functions

high_resolution_clock::now

 

static std::chrono::time_point<std::chrono::high_resolution_clock> now();		(since C++11)

Returns a time point representing with the current point in time.

Parameters

(none)

Return value

A time point representing the current time.

Exceptions

noexcept specification:  

noexcept

  

Example

Run this code

#include <iostream>
#include <vector>
#include <chrono>
 
int main()
{
    for (unsigned long long size = 1; size < 10000000; size *= 10) {
 
        auto start = std::chrono::high_resolution_clock::now();   // a "timepoint" representing now
 
        std::vector<int> v(size, 42);               // something that takes some time to do
 
        auto end = std::chrono::high_resolution_clock::now();     // the new current "timepoint"
 
        auto elapsed = end - start;                 // difference is a "duration"
 
        std::cout << size << ": " << elapsed.count() << '\n';  // clock ticks (seconds)
    }
}

Possible output:

1: 1
10: 2
100: 3
1000: 6
10000: 47
100000: 507
1000000: 4822