Choroba the reason for uninitliazed error that Im getting is because my group hash doesnt have relations which are more than length 3. As you can see below. E.P.E.E is 4 relations. But thats alright as I dont want to have relations which are more than three. But could this also be the reaso n behind the program getting hanged when run on __DATA__ more than 300 lines:- 
Use of uninitialized value in print at checking.pl line 71, <DATA> lin
+e 338.
M61:    M61<-M7<-M28<-M6<-Q = E.P.E.E,
Use of uninitialized value in print at checking.pl line 71, <DATA> lin
+e 338.
M196:   M196<-M53<-M7<-M28<-M6<-Q = E.P.E.Pl.E,

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In reply to Re^8: constructing a tree from csv file by zing
in thread constructing a tree from csv file by zing

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