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<CENTER><FONT color=blue size=+2>Human Gene Functions</FONT></CENTER>
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<CENTER><FONT color=green>Time limit:</FONT> 1 Seconds <FONT
color=green>Memory limit: </FONT>32768K </FONT><BR><FONT
color=green>Total Submit:</FONT> 1051 <FONT color=green>Accepted
Submit:</FONT> 558 </CENTER>
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<P>It is well known that a human gene can be considered as a sequence,
consisting of four nucleotides, which are simply denoted by four letters, A, C,
G, and T. Biologists have been interested in identifying human genes and
determining their functions, because these can be used to diagnose human
diseases and to design new drugs for them. <BR><BR>A human gene can be
identified through a series of time-consuming biological experiments, often with
the help of computer programs. Once a sequence of a gene is obtained, the next
job is to determine its function. One of the methods for biologists to use in
determining the function of a new gene sequence that they have just identified
is to search a database with the new gene as a query. The database to be
searched stores many gene sequences and their functions – many researchers have
been submitting their genes and functions to the database and the database is
freely accessible through the Internet. <BR><BR>A database search will return a
list of gene sequences from the database that are similar to the query gene.
Biologists assume that sequence similarity often implies functional similarity.
So, the function of the new gene might be one of the functions that the genes
from the list have. To exactly determine which one is the right one another
series of biological experiments will be needed. <BR><BR>Your job is to make a
program that compares two genes and determines their similarity as explained
below. Your program may be used as a part of the database search if you can
provide an efficient one. <BR><BR>Given two genes AGTGATG and GTTAG, how similar
are they? One of the methods to measure the similarity of two genes is called
alignment. In an alignment, spaces are inserted, if necessary, in appropriate
positions of the genes to make them equally long and score the resulting genes
according to a scoring matrix. <BR><BR>For example, one space is inserted into
AGTGATG to result in AGTGAT-G, and three spaces are inserted into GTTAG to
result in –GT--TAG. A space is denoted by a minus sign (-). The two genes are
now of equal length. These two strings are aligned: <BR><BR>AGTGAT-G
<BR>-GT--TAG <BR><BR>In this alignment, there are four matches, namely, G in the
second position, T in the third, T in the sixth, and G in the eighth. Each pair
of aligned characters is assigned a score according to the following scoring
matrix. <BR></P>
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<P>* denotes that a space-space match is not allowed. The score of the alignment
above is (-3)+5+5+(-2)+(-3)+5+(-3)+5=9. <BR><BR>Of course, many other alignments
are possible. One is shown below (a different number of spaces are inserted into
different positions): <BR><BR>AGTGATG <BR>-GTTA-G <BR><BR>This alignment gives a
score of (-3)+5+5+(-2)+5+(-1) +5=14. So, this one is better than the previous
one. As a matter of fact, this one is optimal since no other alignment can have
a higher score. So, it is said that the similarity of the two genes is 14.
<BR></P>
<P><BR><B>Input</B> <BR><BR>The input consists of T test cases. The number of
test cases ) (T is given in the first line of the input. Each test case consists
of two lines: each line contains an integer, the length of a gene, followed by a
gene sequence. The length of each gene sequence is at least one and does not
exceed 100. <BR><BR><BR><B>Output </B><BR><BR>The output should print the
similarity of each test case, one per line. <BR><BR><BR><B>Sample Input
</B><BR><BR>2 <BR>7 AGTGATG <BR>5 GTTAG <BR>7 AGCTATT <BR>9 AGCTTTAAA </P>
<P><BR><B>Output for the Sample Input </B></P>
<P>14 <BR>21 </P>
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<FONT color=green size=+1>Problem Source: </FONT><I>Asia 2001, Taejon (South
Korea)</I>
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