C++ chrono::operator==() Function

The std::chrono::operator==() function in C++, is used to compare the two time points or durations for equality. It returns true if the two operands represent the same point in time or duration, otherwise it returns false. It supports different time units such as seconds, milliseconds.

Syntax

Following is the syntax for std::chrono::operator==() function.

bool operator== (const duration<Rep1,Period1>& lhs, const duration<Rep2,Period2>& rhs)

Parameters

• lhs, rhs − It indicates the duration objects.
• r − It indicates a value of an arithmetic type, or an object of a class emulating an arithmetic type.

Return value

This function returns the result of the operation.

Example 1

Let's look at the following example, where we are going to compare the two time points.

#include <iostream>
#include <chrono>
int main() {
   auto x1 = std::chrono::system_clock::now();
   auto x2 = x1;
   if (x1 == x2) {
      std::cout << "The time points are equal.\n";
   } else {
      std::cout << "The time points are different.\n";
   }
   return 0;
}

Output

Output of the above code is as follows −

The time points are equal.

Example 2

Consider the following example, we are going to compare the two durations.

#include <iostream>
#include <chrono>
int main() {
   auto x1 = std::chrono::seconds(120);
   auto x2 = std::chrono::minutes(2);
   if (x1 == x2) {
      std::cout << "The durations are equal.\n";
   } else {
      std::cout << "The durations are different.\n";
   }
   return 0;
}

Output

Following is the output of the above code −

The durations are equal.