#include <bits/stdc++.h> using namespace std; vector <int> adj[10000]; int d[10000]; int dmax = 0; int last0 = 0; int last = 0; string s = "", s1, s2; void f( int n ) { if ( n == 0 ) { return; } while ( n > 0 ) { s += char( ( n % 4 ) + '0' ); n /= 4; } return; } int send_message ( int n, int i, int pi ) { int d1[i + 1]; vector <bool> visited( i + 1, false ); queue <int> q; adj[i].push_back( pi ); adj[pi].push_back( i ); d[i] = d[pi] + 1; if ( d[i] > d[last0] ) { last0 = i; } d1[last0] = 0; q.push( last0 ); dmax = 0; visited[last0] = true; while ( q.size() ) { int x = q.front(); q.pop(); for ( auto y : adj[x] ) { if ( visited[y] == false ) { visited[y] = true; q.push( y ); d1[y] = d1[x] + 1; if ( d1[y] > dmax ) { dmax = d1[y]; last = y; } else if ( d1[y] == dmax ) { last = min( last, y ); } } } } if ( i == 9985 ) { f( last0 ); s1 = s; s = ""; while ( s1.length() < 7 ) { s1 += "0"; } f( last ); s2 = s; while ( s2.length() < 7 ) { s2 += "0"; } } else if ( i > 9985 and i < 9993 ) { if ( last0 == i or last == i ) { if ( last0 == 0 or last == 0 ) { return 4; } else { return last + last0; } } else { return s1[i - 9986] - '0'; } } else if ( i > 9992 ) { if ( last0 == i or last == i ) { if ( last0 == 0 or last == 0 ) { return 4; } else { return last + last0; } } else { return s2[i - 9993] - '0'; } } return 0; } pair <int, int> longest_path ( vector <int> a ) { pair <int, int> answer = {0, 0}; int k = 1; bool b = false; for ( int i = 9986; i < 10000; i++ ) { if ( a[i] == 4 ) { answer = { 0, i }; b = true; } else if ( a[i] > 4 ) { answer = { min( a[i] - i, i ), max( a[i] - i, i ) }; b = true; } else if ( b == false ) { if ( i > 9992 ) { answer.second += a[i] * k; } else { answer.first += a[i] * k; } if ( i == 9992 ) { k = 1; } else { k *= 4; } } } return answer; }