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目录
GoodArray·························································································2
How many Sentences··········································································3
Lottery Coupons·················································································4
Whole Minute Dilemma········································································6
Maximum Substring·············································································8
Shares Purchase·············································································· 10
Caplock··························································································· 12
Meandering array·············································································· 14
Is anagram······················································································ 15
Reverse sentence············································································· 16
Number of pairs················································································ 18
1
GoodArray
2
How many Sentences
Given an array of words and an array of sentences, determine which words are anagrams
of each other. Calculate how many sentences can be created by replacing any word with
one of its anagrams.
Example
wordSet = ['listen', 'it', 'it', 'is']
sentence = 'listen it is silent'
Determine that listen is an anagram of silent. Those two words can be replaced with their
anagrams. The four sentences that can be created are:
•
listen it is silent
•
•
•
listen it is listen
silent it is silent
silent it is listen
Function Description
Complete the countSentences function in the editor below.
3
Lottery Coupons
There is a lottery with n coupons and n people take part in it. Each person picks exactly
one coupon. Coupons are numbered consecutively from 1 to n, n being the maximum ticket
number. The winner of the lottery is any person who owns a coupon where the sum of the
digits on the coupon is equal to s. If there are multiple winners, the prize is split equally
among them. Determine how many values of s therewhere where there is at least one
winner and the prize is split among most people.
Example
n = 12
The list of coupon numbers generated from 1 to n is [1,2,3,4,5,6,7,8,9,10,11,12]. The sums
of the digits are [1,2,3, 4, 5, 6, 7,8,9, 1, 2, 3]. The largest number of winners is 2 which will
occur for coupons numbered [1, 10], [2, 11] and [3, 12]. The maximum number of possible
winners occurs for any of these 3 possible values of s, so 3 is the answer.
Function Description
Complete the function lotteryCoupons in the editor. The function must return the number
of ways to choose s in such a way that there is at least one winner and the prize is split
among the greatest
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5
Whole Minute Dilemma
A music player allows users to choose songs to play but it has some rules. The songs must
be chosen in pairs and the pair's durations must add up to a multiple of 60 seconds (e.g.,
60, 120, 180). Given a list of song durations, calculate the total number of different song
pairs that can be chosen.
Example
n=3
songs = [40, 20, 60]
Only one pair of songs has a combined duration that is a multiple of a whole minute (40+20
= 60) so return 1. While the third song is a single minute long, songs must be chosen in
pairs.
Function Description
Complete the function playlist in the editor below.
playlist has the following parameter(s):
int songs[n]: the song durations in seconds
Returns:
int: the number of valid pairs
6
7
Maximum Substring
A substring is a contiguous sequence of characters within a stringGiven a string determine
the alphabetically maximum substring
Example
s = 'baca'
The unique substrings: ['b', 'bac', 'baca', 'a', 'ac', 'aca', 'c', 'c', 'c
Arranging the substrings alphabetically: ['a', 'ac', 'aca', 'b', 'ba', 'bSac', 'baca', 'ca']
The maximum substring alphabetically: 'ca
Function Description
Complete the function maxSubstring in the editor below.
maxSubstring has the following parameter(s):
string s: a string
Returns
string: the maximum substring in s
Constraints
1<length ofs 100
all characters of s are in the range ascii[a-z]
8
9
Shares Purchase
Every year, an investment firm invests into several companies' shares. Marority of their
investments are in 3 companies: A, B and C. As they inveyesey create a string of all of their
investments in order. Given a string of their investments, determine the number of time
period:s they invested in the three major companies'shares
For example,given the investments as s = "ABBCZBAC", for total number of investments
n=7. Starting from the left, the first substringthat contains an investment in all companies
is "ABBC". There are are13 substrings of swhich meet the criterion: ["ABBC", "ABBCZ",
"ABBCZ"B","АBBCZBA", "ABBCZBAC", "BBCZBA", "BBCZBAC", "BCZ"BAC", "CZBA",
"CZBAC", "ZBAC"
Note: Two substrings are considered different if the starting, ending, orboth positions differ.
Function Description
Complete the function analyzelnvestments in the editor below. Thefunction must return a
long integer. analyzelnvestments has the following parameter(s):
s: a string of length n
Constraints
•
1sns105
•
s[i]E{'A'...'Z'}(where 0 s i < n)
Example 1:
Input: "ABC"
Output: 1
10
Example 2:
Input: "ABCCBA"
Output: 7
Example 3:
Input: "PQACBA"
Output: 7
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Caplock
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13
Meandering array
Took the Hackerrank test for Goldman Sachs NYC New Analyst Engineering Program today.
Both questions were really easy in my opinion.
Question : Meandering array
An array of integers is defined as being meandering order when the first two elements are
the respective largest and smallest elements in the array and the subsequent elements
alternate between its next largest and next smallest elements. In other words, the elements
are in order of [first_largest, first_smallest, second_largest, second_smallest.....]
Example:
The array [-1, 1, 2, 3, -5] sorted normally is [-5, -1, 1, 2, 3].
Sorted in meandering order, it becomes [3, -5, 2, -1, 1]
Constraints:
2 <= n <= 10^4
-10^6 <= unsorted[i] <= 10^6
The unsorted array may contain duplicate elements
14
Is anagram
Given an array of strings strs, group the anagrams together. You can return the answer in
any order.
An Anagram is a word or phrase formed by rearranging the letters of a different word or
phrase, typically using all the original letters exactly once.
Example 1:
Input: strs = ["eat","tea","tan","ate","nat","bat"]
Output: [["bat"],["nat","tan"],["ate","eat","tea"]]
Example 2:
Input: strs = strs = [""]
Output: [[""]]
Example 3:
Input: strs = strs = ["a"]
Output: [["a"]]
15
Reverse sentence
Given a String S, reverse the string without reversing its individualwordsWords are
separated by dots.
Input Format
The input consists of a single line containing a string 'S'.
Output Format:
The output format contains a string which is the reversed version of the given string 'S'
Given:
i.like.this.program.very.much
Output:
much.very.program.this.like.i
Explanation of given Test Cases :
After reversing the whole string(not individual words),the input string becomes much.
very.program.this.like.i
Approach:
•
Initially, reverse the individual words of the given string oneby one, for the above
example, after reversing individual words the string shhould be "i.ekil.siht.margorp.yrev.
hcum".
•
Reverse the whole string from start to end to get the desired output "much.very.
program.this.like.i" in the above example.
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Code:
17
Number of pairs
Given an array of integers, and an integer 'K', find the courint of pairs of elements in the
array whose sum is equal to 'K'.
Input:
First line of the input contains an integer T,denoting the nuimber of test cases. Then T
test cases follow. Each test case consists of twolines. First line of each test case contains
2 space separated integers Nand K denoting the size of array and the sum respectively.
Second line of each test case cortains N space separated integers denoting the elements
of the array.
Output:
Print the count of pairs of elements in the array whose sum isequal to the K.
Constraints:
1<=T<=50
1<=N<=50
1<=K<=50
1<=A[i]<=100
Example:
Input
2
46
1571
42
1111
Output
2
6
18
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