Game on Stick

One free afternoon, Chef found an old board game in his kitchen. He decided to invite his friends Miron and Slava to come play it with him. The board is a rectangular grid of size 2 × N. Initially, Miron and Slava each put their chips at a location (x1,y1 ) and (x2,y2 ) respectively. The game then proceeds as follows : - Each player moves their chip in turns. - In each turn, a player can move