new twice = 0;
     if(cmdtext == "/rules" && twice == 0) {
          twice++;
     } else {
          twice = 0;
          return SendClientMessage(playerid,red,"You've typed /rules twice!");
     }
}

new RulesAmount[MAX_PLAYERS];
 
     OnplayerConnect(playerid)
     {
         RulesAmount[playerid] = 0;
     }


     if(strcmp(cmd, "/rules", true) == 0)
     {
        if(RulesAmount[playerid] <= 1) { RulesAmount[playerid] ++;
        else
        {
             RulesAmount[playerid] = 0;
             return SendClientMessage(playerid,red,"You've typed /rules twice!");
        }
     } 

}

new twice = 0; // Creates a variable with the value 0.
     if(cmdtext == "/rules") { //checks we typed /rules
          if(twice == 0) { //if our variable (twice) is still 0, then it adds one (so twice is 1 now.)
          twice++;
          } else { //Now, we've got the twice 1, and typed /rules, so it returns that message:
          twice = 0; //sets twice 0 to repeat the code.
          return SendClientMessage(playerid,red,"You've typed /rules twice!");//sends this message, and it doesnt perform /rules.
     }
}