My First "post"!

I'm getting unexpected (INCORRECT??!!)
results from the "index" function.

I'm looking for enlightenment.

My code and output follow:

#!/usr/bin/perl -w
                                                                
open (IN, "one.seq.one.line");
open (OUT, ">out.index.pl");
                                                                
                                                                
                                                                
while(<IN>){
                                                                
print OUT $_;
print OUT "The first occurance of little a is: ", index($_,"a"), "\n";
print OUT "The first occurance of little c is: ", index($_,"c"), "\n";
print OUT "The first occurance of little g is: ", index($_,"g"), "\n";
print OUT "The first occurance of little t is: ", index($_,"t"), "\n";
                                                                
print OUT "\n\n";
}

[download]
Here is the output 

ATGGACTGCACCTGGAGGATCCTCTTCTTGGTGGCAGCAGCTACAGgcaagagaatcctgagttccaggg
+ctgatgaggg
The first occurance of little a is: 48
The first occurance of little c is: 47
The first occurance of little g is: 46
The first occurance of little t is: 49

[download]
Note that the last line does NOT give the position of
the first little t (should be 55).
Also note that if I change the order in the code so
that the I put the index($_,"t") line first
(before the other three), then it gives the correct
results.

Thanks much!
Would anyone be willing to use my exact code and
put the above line (starting with ATG...) into
the file "one.seq.one.line", and see if they get
the same results as I did???

I'm an admitted newbie, but my systems administrator
looked at if for about 15 mins this morn and thought
it was funny as well.

Thanks much!!

In reply to Funny results of "index" by jkmiller

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