Issue # 28: IT training - current issues and challenges from leading companies

Questions

Suppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. He then says to you, “Do you want to pick door No. 2? ”
Is it to your advantage to switch your choice?

You have 5 jars of pills. Each pill weighs 10 grams, except for contaminated pills contained in one jar, where each pill weighs 9 grams. Given a scale, how could you tell which jar had the contaminated pills in just one measurement?

Tasks

Given a string S consisting of uppercase alphabetic characters. Return the number of different substrings of size 2 that appear in S as contiguous substrings.

Input: The first line contains 'T' denoting the number of testcases. Then follows description of test cases. The next T lines contains the string S.

Output: Output the number of different substrings of size 2 in S.

Constraints:
1<=T<=50
1<=|S|<=100

Example:
Input:
2
ABCAB
XYZ

Output:
3
2

Explanation: For "ABCAB", the three distinct substrings of size 2 are "AB", "BC" and "CA". For "XYZ", the two distinct substrings of size 2 are "XY" and "YZ".

Given an array arr [] of positive integers. Find the length of the longest sub-sequence such that elements in the subsequence are consecutive integers, the consecutive numbers can be in any order.

Input:
The first line of input contains T, number of test cases. First line of line each test case contains a single integer N.
Next line contains N integer array.

Output:
Print the output of each test case in a seprate line.

Constraints:
1 <= T <= 100
1 <= N <= 105
0 <= a[i] <= 105

Example:
Input:
2
7
2 6 1 9 4 5 3
7
1 9 3 10 4 20 2

Output:
6
4

Explanation:
Testcase 1: The consecutive numbers here are 1, 2, 3, 4, 5, 6. These 6 numbers form the longest consecutive subsquence.

Testcase2: 1, 2, 3, 4 is the longest consecutive subsequence.

Given a string of lowercase ASCII characters, find all distinct continuous palindromic sub-strings of it.

Input:
The first line of input contains an integer T denoting the number of test cases. Then T test cases follow. Each test case contains a string.

Output:
Print the count of distinct continuous palindromic sub-strings of it.

Constraints:
1<=T<=10^5
1<=length of string<=10^5

Example:
Input:
2
abaaa
geek

Output:
5
4

The answers

 for _ in range(int(input())): s = input() ls = [s[i:i+2] for i in range(0,len(s))] del ls[-1] ls = list(set(ls)) print(len(ls)) 

 #include<iostream> using namespace std; int main() { int t; cin >> t; while(t--) { int n; cin >> n; int ar[n]; for(int i=0;i<n;i++) cin >> ar[i]; //************************************* //Finding Max Element of Array int max=-1; for(int i=0;i<n;i++) { if(ar[i]>max) { max=ar[i]; } } //*************************************** int size = max+1; int hash[size]={0}; for(int i=0;i<n;i++) hash[ar[i]]++; //*************************************** /*for(int i=0;i<size;i++) cout << hash[i] << " "; cout << endl;*/ for(int i=0;i<n;i++) { if(hash[ar[i]]>1) hash[ar[i]]=1; } int count = 1,max_count = 1; for(int i=0;i<size;i++) { if(hash[i]==1 && hash[i+1]==1) count++; else { if(count>max_count) max_count=count; count = 1; } } cout << max_count << endl; } } 

 #include<bits/stdc++.h> using namespace std; bool ispalindrome(string s) { int i=0;int j=s.length()-1; while(i<j) { if(s[i]!=s[j]) return false; i++; j--; } return true; } int main() { //code int t; cin>>t; while(t--) { string s; cin>>s; vector<string>ans; for(int l=1;l<=s.length();l++) { for(int i=0;i<s.length()-l+1;i++) { if(ispalindrome(s.substr(i,l))) ans.push_back(s.substr(i,l)); } } sort(ans.begin(),ans.end()); ans.erase(unique(ans.begin(),ans.end()),ans.end()); cout<<ans.size()<<endl; } return 0; }