Four in Line

The goal of Four in Line is to align four pieces on a board consisting of six rows and seven columns. Each player has 21 cards of a color. In turns, players must enter a record in the column that prefer (provided it is not complete) and it will fall to the lowest position. Win the game to get the first line four consecutive chips of the same color in horizontal, vertical or diagonal. If all columns are full but no one has made a valid row, no tie.