One day, in the wide ocean there were often fights between the Sura Shark and the Baya Crocodile. They fight just because they are fighting for prey. Both are equally strong, equally agile, equally intelligent, equally vicious and equally greedy. They have fought many times and no one has won or lost. They finally made a deal

I'm tired of constantly fighting, Baya.

Sura, I'm the same way. What should we do to stop fighting?

We should split the region into two halves to avoid a battle between us. 

i agree with you, Sura

I have complete control over the water and must seek prey in the water, but you have complete control over the land and must seek prey on the land. We define the boundary between land and water as the location reached by sea water at low tide!

Sure! We won't fight anymore if the area is divided in this way.

There will be no more battles between Sura and Baya now that the region has been divided. Both parties have agreed to respect each other's space.

But one day, Sura was looking for prey in the river. This is done secretly so that Baya does not know. At first this was not known. But one day Baya caught Sura's actions. Of course Baya was very angry to see Sura breaking his promise.

Sura, why did you break the rules that we both agreed on? Why do you dare to enter the river that is my territory?