HackerEarth String Algorithm Problems

Author: OmkarPathak

CompetitiveProgramming/HackerEarth/Algorithms/String/P01_SortSubtring.py

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+# Given a string S, and two numbers N, M - arrange the characters of string in between the indexes N
+# and M (both inclusive) in descending order. (Indexing starts from 0).
+#
+# Input Format:
+# First line contains T - number of test cases.
+# Next T lines contains a string(S) and two numbers(N, M) separated by spaces.
+#
+# Output Format:
+# Print the modified string for each test case in new line.
+#
+# Constraints:
+#
+# 1≤T≤1000
+# 1≤|S|≤10000 // |S| denotes the length of string.
+# 0≤N≤M<|S|
+# S∈[a,z]
+#
+# SAMPLE INPUT
+# 3
+# hlleo 1 3
+# ooneefspd 0 8
+# effort 1 4
+#
+# SAMPLE OUTPUT
+# hlleo
+# spoonfeed
+# erofft
+
+for i in range(int(input())):
+    user_input = input()
+    user_input = user_input.split()
+    to_char = int(user_input[2])
+    from_char = int(user_input[1])
+    string = user_input[0][from_char:to_char + 1]
+    replace = ''.join(sorted(string)[::-1])
+    print(user_input[0][:from_char] + replace + user_input[0][to_char + 1:len(user_input[0])])

CompetitiveProgramming/HackerEarth/Algorithms/String/P02_PrintFirstOccurence.py

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+# Given a string containing only lower case letters ,print first occurrence of all the letters present
+#  in that order only.
+#
+# Input :
+#
+# Test cases, t
+# string ,s
+# Output :
+#
+# Desired Output
+#
+# Constraint :
+#
+# string length <=200
+#
+# SAMPLE INPUT
+# 2
+# aasdvasvavda
+# sajhags
+#
+# SAMPLE OUTPUT
+# asdv
+# sajhg
+#
+
+for _ in range(int(input())):
+    user_input = input()
+    string = []
+    for i in range(len(user_input)):
+        if user_input[i] not in string:
+            string.append(user_input[i])
+
+    print(''.join(string))

CompetitiveProgramming/HackerEarth/Algorithms/String/P03_MonkTeachesPalindrome.py

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+# Monk introduces the concept of palindrome saying,"A palindrome is a sequence of characters which reads the s
+# ame backward or forward."
+# Now, since he loves things to be binary, he asks you to find whether the given string is palindrome or not.
+# If a given string is palindrome, you need to state that it is even palindrome (palindrome with even length)
+# or odd palindrome (palindrome with odd length).
+#
+# Input:
+# The first line consists of T, denoting the number of test cases.
+# Next follow T lines, each line consisting of a string of lowercase English alphabets.
+#
+# Output:
+# For each string , you need to find whether it is palindrome or not.
+# If it is not a palindrome, print NO.
+# If it is a palindrome, print YES followed by a space; then print EVEN it is an even palindrome
+# else print ODD.
+# Output for each string should be in a separate line.
+# See the sample output for clarification.
+#
+# Constraints:
+# 1≤T≤50
+# 1≤length of string≤105
+#
+# SAMPLE INPUT
+# 3
+# abc
+# abba
+# aba
+#
+# SAMPLE OUTPUT
+# NO
+# YES EVEN
+# YES ODD
+
+for _ in range(int(input())):
+    user_input = input()
+    if user_input == user_input[::-1]:
+        if len(user_input) % 2 == 0:
+            print('YES EVEN')
+        else:
+            print('YES ODD')
+    else:
+        print('NO')

CompetitiveProgramming/HackerEarth/Algorithms/String/P04_DNAPride.py

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+# Everyone is familiar with Pratik's obsession with DNA and how much he likes to find the correct pair for
+# the nucleotide bases. One day Samim found him exaggerating about his knowledge of DNA bases. So Samim
+# challenged Pratik about finding the correct base pair for the given DNA sequence and show the result.
+# Also he secretly introduced some of RNA nucleotide bases to test Pratik. Now initially he accepted the
+# challenge but soon found out about how big the sequence actually was, so he came to you ask him for your
+# in finding the sequence and keep his pride about the knowledge of DNA molecules.
+#
+# You are given a string that contains the nucleotide bases of DNA and RNA, you are needed to find the
+# correct pair for all the bases and print the corresponding sequence obtained. In case the sequence
+# contains a RNA base, print "Error RNA nucleobases found!" (without quotes).
+#
+# INPUT FORMAT
+#
+# The first line of input contains T, the no of test cases. The next line of input contains N, the no of
+# bases in each of the DNA sequence The line after that contains the DNA sequence.
+#
+# OUTPUT FORMAT
+#
+# For each test case output your answer on a new line.
+#
+# CONSTRAIN
+#
+# 1≤T≤10^4
+# 1≤N≤10^6
+#
+# SAMPLE INPUT
+# 3
+# 2
+# AG
+# 4
+# ATGC
+# 6
+# UGCACT
+#
+# SAMPLE OUTPUT
+# TC
+# TACG
+# Error RNA nucleobases found!
+
+for _ in range(int(input())):
+    string_length = int(input())
+    string = input()
+    check = {'A':'T', 'T':'A', 'G':'C', 'C':'G'}
+    result = []
+
+    if 'U' in string:
+        print('Error RNA nucleobases found!')
+    else:
+        for i in range(len(string)):
+            result.append(check[string[i]])
+
+        print(''.join(result))

CompetitiveProgramming/HackerEarth/Algorithms/String/P05_VowelPhobia.py

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+# Manish has got the task to frame a speech for his professor at the university at the Annual sports meet.But
+# the problem is that the professor has speech dyslexia and he can't speak the words clearly which have vowels
+# in them. So Manish has to avoid such words and has to minimise their usage in the speech letter. Your task
+# is to help Manish mark the vowels in the words so that he can minimise their use. You are given a string S
+# consisting of lower case letters only. You need to count the number of vowels in the string S.
+#
+# INPUT The first line will contain an integer T denoting the number of test cases. The following T lines
+# will contain a string S in lower case letters only.
+#
+# OUTPUT Print the number the vowels in the string S.
+#
+# CONSTRAINTS 1<=T<=100
+#
+# SAMPLE INPUT
+# 1
+# hashes
+#
+# SAMPLE OUTPUT
+# 2
+
+for _ in range(int(input())):
+    string = input()
+    count = 0
+    for i in range(len(string)):
+        if string[i] in ['a', 'e', 'i', 'o', 'u']:
+            count += 1
+
+    print(count)

CompetitiveProgramming/HackerEarth/Algorithms/String/P06_NobitaAndString.py

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+# Doraemon gave Nobita a gadget that swaps words inside a string in the following manner :
+#
+# If there are W words, word 1 is swapped with word W, word 2 is swapped with word W-1 and so on. The
+# problem is that Nobita himself cannot verify the answer for large strings. Help him write a program to do so.
+#
+# INPUT :
+# the first line of the input contains the number of test cases. Each test case consists of a single line
+# containing the string.
+#
+# OUTPUT :
+# output the string with the words swapped as stated above.
+#
+# CONSTRAINTS :
+# |string length| <= 100000
+# string contains english alphabets and spaces
+#
+# SAMPLE INPUT
+# 1
+# hello world
+#
+# SAMPLE OUTPUT
+# world hello
+
+for _ in range(int(input())):
+    string = input().split()
+    print(' '.join(string[::-1]))