[Vince]

Make a per-player variable (checkpointid[MAX_PLAYERS], for example) in which you'll store the player's current checkpoint.
Whenever a player passes trough a checkpoint, increment the var with 1. You can then use it to set the next checkpoint accordingly.

pawn Код:

switch(checkpointid)
{
    // Add CP's
    case 1: SetPlayerCheckpoint(...);
    case 2: SetPlayerCheckpoint(...);
    case 3: SetPlayerCheckpoint(...);
}