Poorva Express: हुगली सी बहती तेरी चाल है पूर्वा तू बेमिसाल है - Keshav Singh

Na I feel it's Black Diamond! This is because:-
1> Excepting Rake Maintainance there is no daily expenditure for Black (Blankets, Mattresses and pillows not required in Black Diamond.
2> The Income per Km of Black > Allepey because:-
a> Black is a SF which ALLP isn't:-
b>...
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Black has 22 coaches, ALLP has 10 or 12 (DHN rake)
c> Black is way more jampacked than ALLP, in other words having almost 19 General coaches means Black can carry way more passengers than ALLP Exp.
d> By the time ALLP completes it's trip Black has made approx 5 trips already. Railway tickets don't increase in price, proportionatly to distance travel. So Black wins easily again.
3> The Cost of managing a pantry car in the DHN-ALLP Exp!