four segments are needed
There are seven columns and six rows.
In the game Connect Four, there are a total of 42 checker pieces used during play—21 for each player. The game is played on a vertical grid with six rows and seven columns, where players take turns dropping their pieces into the columns. The objective is to connect four of one's own pieces in a row, either horizontally, vertically, or diagonally.
Assuming that each bridge can connect at most two vertices, you will need at least 4 bridges to connect seven vertices. Conversely, two bridges will connect at most four vertices.
Four Chords That Made a Million was created in 2000-04.