[Vince]

pawn Код:

stock Float:GetDistanceBetweenPoints(Float:x1, Float:y1, Float:z1, Float:x2, Float:y2, Float:z2)
{
    x1 -= x2;
    y1 -= y2;
    z1 -= z2;
    return floatsqroot((x1 * x1) + (y1 * y1) + (z1 * z1));
}

Then just find the car that is the least far away from the player.