Difference between revisions of "Template:cpp/chrono/clock/now"
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{ | { | ||
for (unsigned long long size = 1; size < 10000000; size *= 10) { | for (unsigned long long size = 1; size < 10000000; size *= 10) { | ||
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| − | auto elapsed = end - start; | + | auto start = std::chrono::{{{1}}}::now(); // a "timepoint" representing now |
| − | std::cout << size << ": " << elapsed.count() << '\n'; | + | |
| + | std::vector<int> v(size, 42); // something that takes some time to do | ||
| + | |||
| + | auto end = std::chrono::{{{1}}}::now(); // the new current "timepoint" | ||
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| + | auto elapsed = end - start; // difference is a "duration" | ||
| + | |||
| + | std::cout << size << ": " << elapsed.count() << '\n'; // clock ticks (seconds) | ||
} | } | ||
} | } | ||
Revision as of 14:19, 20 April 2014
| static std::chrono::time_point<std::chrono::{{{1}}}> now(); |
(since C++11) | |
Returns a time point representing with the current point in time.
Contents |
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::{{{1}}}::now(); // a "timepoint" representing now std::vector<int> v(size, 42); // something that takes some time to do auto end = std::chrono::{{{1}}}::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
