[ns] prob. in printing the links costs.

[mahesh@cs.iitm.ernet.in]

hi seniors,
	i'm doing multicasting simulation, in which i'm struck up by
a problem in printing the cost of the links. I have used a while loop to
print the cost of the links and i'm getting the following error. For the
first time when the loop iterates the cost got printed and from the next
iteration it is giving the following error

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invalid command name ""
    while executing
"[$ns link $n($n2) $n($i)] cost?"
    ("while" body line 2)
    invoked from within
"while {$i < 11} {
puts [[$ns link $n($n2) $n($i)] cost?]
set i [expr $i+1]
}"
    (file "mcast2.tcl" line 101)

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