LeetCode içerisinde bulunan “Base 7” sorusunun açıklaması ve çözümü. Bu soruda size verilen 32-bit integer değerin 7 tabanında gösterimini geriye döndürmeniz isteniyor.
► LeetCode 504. Base 7: https://leetcode.com/problems/base-7/
► Problem açıklaması:
Given an integer num, return a string of its base 7 representation.
Example 1:
Input: num = 100
Output: “202”
Example 2:
Input: num = -7
Output: “-10”
Constraints:
-10^7 lessEqual num lessEqual 10^7
HackerRank içerisinde bulunan “Super Reduced String” sorusunun açıklaması ve çözümü. Bu soruda size verilen bir string‘in içerisinde, yan yana olan aynı karakterlerin silinerek elde edilebilecek son string’i bulmanız isteniyor.
► HackerRank – Super Reduced String: https://www.hackerrank.com/challenges/reduced-string/problem
► Problem açıklaması:
Reduce a string of lowercase characters in range ascii[‘a’..’z’]by doing a series of operations. In each operation, select a pair of adjacent letters that match, and delete them.
Delete as many characters as possible using this method and return the resulting string. If the final string is empty, return Empty String
Example.
s = “aab”
aab shortens to b in one operation: remove the adjacent a characters.
s = “abba”
Remove the two ‘b’ characters leaving ‘aa’. Remove the two ‘a’ characters to leave ”. Return ‘Empty String’.
Function Description
Complete the superReducedString function in the editor below.
superReducedString has the following parameter(s):
string s: a string to reduce
Returns
string: the reduced string or Empty String
Sample Input 0
aaabccddd
Sample Output 0
abd
Explanation 0
Perform the following sequence of operations to get the final string:
aaabccddd → abccddd → abddd → abd
Sample Input 1
aa
Sample Output 1
Empty String
Explanation 1 aa → Empty String
Sample Input 2
baab
Sample Output 2
Empty String
Explanation 2
baab → bb → Empty String
LeetCode içerisinde bulunan “Reverse Vowels of a String” sorusunun açıklaması ve çözümü. Bu soruda size verilen bir string içerisindeki ünlü harfleri tersten yazdırmanız isteniyor.
► LeetCode 345. Reverse Vowels of a String: https://leetcode.com/problems/reverse-vowels-of-a-string/
► Problem açıklaması:
Given a string s, reverse only all the vowels in the string and return it.
The vowels are ‘a’, ‘e’, ‘i’, ‘o’, and ‘u’, and they can appear in both cases.
Example 1:
Input: s = “hello”
Output: “holle”
Example 2:
Input: s = “leetcode”
Output: “leotcede”
Constraints:
1 <= s.length <= 3 * 105
s consist of printable ASCII characters.
HackerRank içerisinde bulunan “Grading Students” sorusunun açıklaması ve çözümü. Bu soruda size verilen sınav sonuçlarını, aşağıda yazılan kurallara göre yuvarlamanız isteniyor.
► HackerRank – Grading Students: https://www.hackerrank.com/challenges/grading/problem
► Problem açıklaması:
HackerLand University has the following grading policy:
– Every student receives a in the inclusive range from 0 to 100.
– Any grade less than 40 is a failing grade.
Sam is a professor at the university and likes to round each student’s according to these rules:
– If the difference between the grade and the next multiple of 5 is less than 3, round grade up to the next multiple of 5.
– If the value of grade is less than 38, no rounding occurs as the result will still be a failing grade.
Examples
grade = 84 round to (85 – 84 is less than 3)
grade = 29 do not round (result is less than 40)
grade = 57 do not round (60 – 57 is 3 or higher)
Given the initial value of grade for each of Sam’s n students, write code to automate the rounding process.
Function Description
Complete the function gradingStudents in the editor below.
gradingStudents has the following parameter(s):
int grades[n]: the grades before rounding
Returns
int[n]: the grades after rounding as appropriate
Sample Input 0
4
73
67
38
33
Sample Output 0
75
67
40
33
HackerRank içerisinde bulunan “CamelCase” sorusunun açıklaması ve çözümü. Bu soruda size camelCase olarak yazılmış bir string’in içerisinde kaç adet kelime olduğunu bulmanız isteniyor.
► HackerRank – CamelCase: https://www.hackerrank.com/challenges/camelcase/problem
► Problem açıklaması:
There is a sequence of words in CamelCase as a string of letters, s, having the following properties:
– It is a concatenation of one or more words consisting of English letters.
– All letters in the first word are lowercase.
– For each of the subsequent words, the first letter is uppercase and rest of the letters are lowercase.
Given s, determine the number of words in s.
Example
s = oneTwoThree
There are 3 words in the string: ‘one’, ‘Two’, ‘Three’.
Function Description
Complete the camelcase function in the editor below.
camelcase has the following parameter(s):
string s: the string to analyze
Returns
int: the number of words in s.
Sample Input
saveChangesInTheEditor
Sample Output
5
Explanation
String s contains five words:
1. save
2. Changes
3. In
4. The
5. Editor
LeetCode içerisinde bulunan “Keyboard Row” sorusunun açıklaması ve çözümü. Bu soruda size verilen bir string dizisi içerisinde, Amerikan klavyesi üzerinde aynı satırdaki harflerden oluşan string’leri geri döndürmeniz isteniyor.
► LeetCode 500. Keyboard Row: https://leetcode.com/problems/keyboard-row/
► Problem açıklaması:
Given an array of strings words, return the words that can be typed using letters of the alphabet on only one row of American keyboard like the image below.
In the American keyboard:
the first row consists of the characters “qwertyuiop”,
the second row consists of the characters “asdfghjkl”, and
the third row consists of the characters “zxcvbnm”.
Example 1:
Input: words = [“Hello”,”Alaska”,”Dad”,”Peace”]
Output: [“Alaska”,”Dad”]
Example 2:
Input: words = [“omk”]
Output: []
Example 3:
Input: words = [“adsdf”,”sfd”]
Output: [“adsdf”,”sfd”]
Constraints: 1 <= words.length <= 20
1 <= words[i].length <= 100
words[i] consists of English letters (both lowercase and uppercase).
HackerRank içerisinde bulunan “Fibonacci Modified” sorusunun açıklaması ve çözümü. Bu soruda fibonacci serisinin değiştirilmiş hali olarak, bir önceki sayının kendisi değil de karesinin toplamı şeklinde çözüm bulmanız isteniyor.
► HackerRank – Fibonacci Modified: https://www.hackerrank.com/challenges/fibonacci-modified/problem
► Problem açıklaması:
Implement a modified Fibonacci sequence using the following definition:
t(i + 2) = t(i) + t(i + 2)^2
Given three integers, t1, t2, and n, compute and print the nth term of a modified Fibonacci sequence.
Function Description
Complete the fibonacciModified function in the editor below. It must return the nth number in the sequence.
fibonacciModified has the following parameter(s):
int t1: an integer
int t2: an integer
int n: the iteration to report
Returns
int: the nth number in the sequence
Note: The value of t[n] may far exceed the range of a 64-bit integer. Many submission languages have libraries that can handle such large results but, for those that don’t (e.g., C++), you will need to compensate for the size of the result.
Sample Input
0 1 5
Sample Output
5
LeetCode içerisinde bulunan “Power of Four” sorusunun açıklaması ve çözümü. Bu soruda size verilen 32-bit signed bir tam sayının 4’ün tam kuvveti olup olmadığını bulmanız isteniyor.
► LeetCode 342. Power of Four: https://leetcode.com/problems/power-of-four/
► Problem açıklaması:
Given an integer n, return true if it is a power of four. Otherwise, return false.
An integer n is a power of four, if there exists an integer x such that n == 4^x.
Example 1:
Input: n = 16
Output: true
Example 2:
Input: n = 5
Output: false
Example 3:
Input: n = 1
Output: true
Constraints: -2^31 lessEqual n lessEqual 2^31 – 1
LeetCode içerisinde bulunan “Reverse Bits” sorusunun açıklaması ve çözümü. Soruda size verilen 32-bit unsigned bir tam sayının bitlerini tersine çevirmeniz isteniyor.
► LeetCode 190. Reverse Bits: https://leetcode.com/problems/reverse-bits/
► Problem açıklaması:
Reverse bits of a given 32 bits unsigned integer.
Note:
Note that in some languages such as Java, there is no unsigned integer type. In this case, both input and output will be given as a signed integer type. They should not affect your implementation, as the integer’s internal binary representation is the same, whether it is signed or unsigned. In Java, the compiler represents the signed integers using 2’s complement notation. Therefore, in Example 2 above, the input represents the signed integer -3 and the output represents the signed integer -1073741825.
Follow up:
If this function is called many times, how would you optimize it?
Example 1:
Input: n = 00000010100101000001111010011100
Output: 964176192 (00111001011110000010100101000000)
Explanation: The input binary string 00000010100101000001111010011100 represents the unsigned integer 43261596, so return 964176192 which its binary representation is 00111001011110000010100101000000.
Example 2:
Input: n = 11111111111111111111111111111101
Output: 3221225471 (10111111111111111111111111111111)
Explanation: The input binary string 11111111111111111111111111111101 represents the unsigned integer 4294967293, so return 3221225471 which its binary representation is 10111111111111111111111111111111.
Constraints:
The input must be a binary string of length 32.
HackerRank içerisinde bulunan “Extra Long Factorials” sorusunun açıklaması ve çözümü. Bu soruda size verilen bir tam sayının faktöriyelini bulmanız isteniyor. Bazı inputlar için faktöriyel 64-bit tam sayıyı aşabilir, bu yüzden daha büyük bir tam sayı tipi kullanmanız gerekiyor.
► HackerRank – Extra Long Factorials: https://www.hackerrank.com/challenges/extra-long-factorials/problem
► Problem açıklaması:
The factorial of the integer n, written n!, is defined as:
n! = n * (n – 1) * (n – 2) * … * 3 * 2 * 1
Function Description
Complete the extraLongFactorials function in the editor below. It should print the result and return.
extraLongFactorials has the following parameter(s):
n: an integer
Note: Factorials of n biggerThan 20 can’t be stored even in a 64-bit long long variable. Big integers must be used for such calculations. Languages like Java, Python, Ruby etc. can handle big integers, but we need to write additional code in C/C++ to handle huge values.
We recommend solving this challenge using BigIntegers.