[Nibblet]

Maybe this?

pawn Код:

forward Float:GetDistanceBetweenPlayers(playerid,targetplayerid);

public Float:GetDistanceBetweenPlayers(playerid,targetplayerid)
{
    new Float:x1,Float:y1,Float:z1,Float:x2,Float:y2,Float:z2;
    if(!IsPlayerConnected(playerid) || !IsPlayerConnected(targetplayerid)) {
        return -1.00;
    }
    GetPlayerPos(playerid,x1,y1,z1);
    GetPlayerPos(targetplayerid,x2,y2,z2);
    return floatsqroot(floatpower(floatabs(floatsub(x2,x1)),2)+floatpower(floatabs(floatsub(y2,y1)),2)+floatpower(floatabs(floatsub(z2,z1)),2));
}