$=0($I$)$ Codewriting

SEttinas

You're creating a new programming language with

some exciting new featurest Any programming

language caffcheck if two strings are matching, but

you'd like yours to be able to check if they're almost

matching. More specifically, we'll say two strings are

almost matching if they're equal in length and all of

their corresponding characters are the same except

for one. For example, "cat" and "bat" are

almost matching, but "cat" and "dog" are not.

For the sake of efficiency, you're planning on testing

the feature by using a single string and comparing its

substrings. Given a string s and an integer $k.$

your task is to find the number of pairs of substrings

of s that are almost matching but differ at their

$k^{th}$ character $(0-$based$).$ It's necessary that the

length of both substrings exceeds k $($otherwise the

strings wouldn't have a $k^{th}$ character$).$

Also note that substrings are determined by their

indices, so there could potentially be multiple

instances of the same word. For example, in the

word "ingratiating" the substring "ing"

$1$ int solution

app.codesignal.com$/$test$/$wYaXziRpWKhiWXt$3$b$/$question$/$K$36$biX$4$EgomKn

ACK TO CUESTIONS

SC

$=3$

$("$ab$","$ac$")-$ i $=4,$ j$=5,1=2,m=3.$

Input$/$Output

$[$execution time limit$]0\mathrm{.}5$ seconds $($cpp$)$

$[$memory limit$]1$ GB

$[$input$]$ string s

A string consisting only of lowercase English letters.

Guaranteed constraints

$15.$ length $200$

$[$input$]$ integer $k$

Guaranteed constraints:

$0k$

$[output]$ integer

The amount $of$ different pairs $as$ described above.

TESTS

CUSTOA TESTS

$3.$ MORE