In this lab, you are asked to complete similars.c program file which has been already given in LMS$.$ In this

program, there are four functions, namely, main, hash$\_$text, strong$\_$similar, and weak$\_$similar. main

function is already provided, and it is supposed to remain as it is $($you should not change it$).$ You are

required to implement hash$\_$text, strong$\_$similar, and weak$\_$similar functions.

Here are the operations performed in main function:

$$ An array of strings with name list with the size $10$ is created to hold name and surname

data in $$name$\_$surname$$ format and the elements are read into it$.$

$$ An array of integers with name hashed$\_$vals is created to hold hashed values of name and and

surname in unsigned integer format.

$$ A two$-$dimensional array of integers to keep the mapping of similarities between each name

surname pair.

$$ hashed$\_$vals array is initialize by calling hash$\_$text function to calculate the hash values of full

name and surname pair.

$$ strong$\_$similar function is called to find the same names and fill the two$-$dimensional array called

same to keep the mapping of similarities.

$$ The name surname pairs, the calculated hash values and similarity mapping is printed on the

standard output.

$$ weak$\_$similar function is called to calculate the hash values of each name and surname separately,

then build the similarity map using hash values.

$$ The name surname pairs, and weakly similarity mapping is printed on the standard output.

$$ average$\_$similarity function calculates the average similarity between pairs of strings based on the

values in the same matrix, which represents strong and weak similarities between strings.

Task $1$: Implement hash$\_$text function.

unsigned int hash$\_$text $($char $*$ list$)$ ;

A character pointer holding names and surnames is sent as an input, and the hash value of the input text

is returned. During the calculation a basic formula is used as follows when the name is ali. The ascii code

for a is $97,$ for l is $108$ and for i is $105.$ The function calculates the hash value by the following formula;

hash $=46$

$2*97+46*108+105$

The algorithm should be applied to all symbols including whitespaces between name and surname. At the

end mod $1000$ of hash value should be returned.

hash $=$ hash mod $1000$

Computer Engineering Department

TED University

Task $2$: Implement strong$\_$similar function.

void strong$\_$similar $($int hval$[$MAX$\_$ELEM$],$ int map$[$MAX$\_$ELEM$][$MAX$\_$ELEM$],$ int $*$strong$\_$count$)$ ;

Calculated hash values of all names$-$surnames pair are sent to the function. The function modifies and

returns the map of exact matches. Exact matching of the entries is calculated only by using hashed values.

Also, you will find the strong similarity count.

Task $3$: Implement weak$\_$similar function.

void weak$\_$similar $($char list$[$MAX$\_$ELEM$][$STR$\_$LEN$],$int map$[$MAX$\_$ELEM$][$MAX$\_$ELEM$])$;

Array of names and surnames list is sent as input and previously calculated similarity map is sent as inputoutput parameter.

During the execution of the function strtok function is used to split names and surnames by using the

space between them. To store the splitted names and surnames a three$-$dimensional array is created. First

dimension is same as the list in main function, second dimension is two either to point name string or

surname string. Similarly, two$-$dimensional array is created to keep hash values of names and surnames

for each pair.

The function then calculates hash values of names and surnames for each pair by calling hash$\_$text

function. Once the hash values of all names and surnames are calculated the function updates the map

array to mark the weak similarities $($either names or surnames are same$).$ For example;

ali kemal and mustafa kemal are weakly similar. They both are weakly similar to kemal ahmet.