Version 5.0 The LEDA User Manual

4.16 Timer ( timer )
1. Definition
The class timer facilitates time measurements. An instance t has two states: running
or stopped. It measures the time which elapses while it is in the state running. The
state depends on a (non-negative) internal counter, which is incremented by every start
operation and decremented by every stop operation. The timer is running iff the counter
is not zero. The use of a counter (instead of a boolean flag) to determine the state is
helpful when a recursive function f is measured, which is shown in the example below:
#include
leda::timer f_timer;
void f()
{
f_timer.start();
// do something ...
f(); // recursive call
// do something else ...
}
f_timer.stop(); // timer is stopped when top-level call returns
int main()
{
f();
std::cout