"Use of uninitialized value" is a warning, not an error. Line 31 of your posted program is 
close INFILE;

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so you are probably running a different version of the code.
Another suspicious thing is your open: do you really prepend a space to the argument?

In reply to Re^3: find the continuity in the data file by choroba
in thread find the continuity in the data file by extrem

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