To clarify that a bit, the program can be reduced to:

my %STUDQT;
$STUDQT{11} =  [qw/fname mname/];
$STUDQT{11}[1][2] =  0;
#$STUDQT{12} =  [qw/fname mname/];
$STUDQT{12}[1][2] =  0;

print
    qq|\$STUDQT{11}[1][2] = $STUDQT{11}[1][2]\n|,
    qq|\t\$STUDQT{12}[1][2] = $STUDQT{12}[1][2]\n|;
$STUDQT{11}[1][2] = 'hello'; #Problem
print
    qq|\$STUDQT{11}[1][2] = $STUDQT{11}[1][2]\n|,
    qq|\t\$STUDQT{12}[1][2] = $STUDQT{12}[1][2]\n|;

__END__

[download]
Don't use strict and run it as is:
$STUDQT{11}[1][2] = 0
    $STUDQT{12}[1][2] = 0
$STUDQT{11}[1][2] = hello
    $STUDQT{12}[1][2] = 0

[download]
Just as we expect. But uncomment: #$STUDQT{12} =  [qw/fname mname/]; and we get: 
$STUDQT{11}[1][2] = 0
    $STUDQT{12}[1][2] = 0
$STUDQT{11}[1][2] = hello
    $STUDQT{12}[1][2] = hello

[download]

Turning on strict reveals that we are attempting to use 'mname' as a symbolic reference and perl guesses what we are attempting as tilly mentioned.

HTH,
Charles K. Clarkson

In reply to Re: Re (tilly) 1: associative array problem by CharlesClarkson
in thread associative array problem by Gerryjun

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