Freaks City

Problem Definition Given a list of accounts accounts, where each accounts[i] is a list of strings. The first string accounts[i][0] is the user's name. The remaining strings are email addresses belonging to that account. The objective is to merge accounts that belong to the same user. Two accounts belong to the same person if they share at least ...

Given an integer \( n \), construct a permutation of \( 1 \) to \( n \) such that for every interval \([l, r]\), the bitwise OR of elements in the interval is at least the length of the interval. The problem contains multiple test cases. The solution is straightforward: the identity permutation \( (1, 2, \ldots, n) \) satisfies the condition. T ...

Problem 2810 - Faulty Keeyboard Simulate the keyboard behavior as described. When encuontering character 'i', reverse the current string. class Solution { public: string finalString(string input) { string result = ""; for(char c : input) { if(c == 'i') { reverse(result.begin(), ...

Prüfer sequences are defined only for trees with \(n>1\) vertices. For the case \(n=1\), special handling is required. A Prüfer sequence establishes a bijection between labeled rooted trees on \(n\) vertices and sequences of length \(n-2\) drawn from \([1,n]\cap\Z\). This encoding transforms tree structures into arrays, which proves invaluab ...

Probabilistic Path Enumeration in Directed Acyclic Graphs Given a directed acyclic graph (DAG) consisting of $V$ vertices and $E$ edges, each edge $e_k$ possesses an independent activation probability $p_k$. The objective is to compute the expected number of functional paths originating from vertex $0$ and terminating at vertex $V-1$. A path is ...

A – Calendar Game Ignoring the year, the losing positions follow the pattern (month + day) % 2 == 1, except for the two special dates 9/30 and 11/30 which allow the next player to flip the parity. #include <bits/stdc++.h> using namespace std; int main() { ios::sync_with_stdio(false); cin.tie(nullptr); int t; cin >> t; ...