An old man sold doughnut on the side of pedestrian. It’s 1 $ per doughnut. A young man jogged there one day and he gave 1 $ but he didn’t take the doughnut. Then it became a routine, everyday the young man came and gave the old man 1 $.
Until one day, after giving 1 $ the young man continued running. But this time the old man ran following him. When the young man knew that, he stopped and waited him.
The old man finally caught him, with short breath because of running the old man try to speak
“Y.. y… young man,,, .Don’t you know,,, “
“One doughnut now is 2 $”.