[Deduction]

Edit: NVM You already solved it xD

Where the player logs in, just put this code:

pawn Код:

new string[128], name;
    if(!IsAdmin){ //Check if Player is not Admin, could be set to !PlayerInfo[playerid][pAdmin] > 0
    GetPlayerName(playerid, name, sizeof(name));
    format(string, sizeof(string), "%s has logged in.", GetPlayerName(playerid));
    SendClientMessageToAll(COLOR_YELLOW, string); }
    else {
    GetPlayerName(playerid, name, sizeof(name));
    format(string, sizeof(string), "[Admin] %s has logged in.", GetPlayerName(playerid));
    SendClientMessageToAll(COLOR_YELLOW, string);}

Just adjust the color to what you want!