Exotic 2D array element referencing

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• C++ increment with macro

  I have the following code and I want to use increment with macro:

  #include <iostream>
  
  #define ABS(x) ((x) < 0 ? -(x) : (x))
  
  int main(int argc, char** argv)
  {
      int x = 5;
      const int result = ABS(x++);
  
      std::cout << "R: " << result << std::endl;
      std::cout << "X: " << x << std::endl;
  
      return EXIT_SUCCESS;
  }
  

  But output will be incorrect:

  R: 6
  X: 7
  

  Is it possible to somehow use macros with an increment, or should this be abandoned altogether?
• Can anyone pls tell me whats wrong with my code ? im stuck for the last 3 hours ,this question is bipartite graph in c++

  idk why im getting error ,can someone help ? im trying to prove if a graph is bipartite or not in c++

  
  bool isBipartite(vector<int> graph[],int V)
  {
      vector<int> vis(V,0);
      vector<int> color(V,-1);
      
      color[0]=1;
      queue <int> q;
      q.push(0);
      while (!q.empty())
      {
          int temp = q.front();
          q.pop();
          for (int i=0;i<V;i++)
          {
              if (!vis[i] && color[i] == -1)   "if there is an edge, and colour is not assigned"
              {
                  color[i] = 1 - color[temp];
                  q.push(i);
                  vis[i]=1;
              }
              else if (!vis[i] && color[i] == color[temp] "if there is an edge and both vertices have same colours"
              {
                  vis[i]=1;
                  return 0;                                // graph is not bipartite
              }
                  
              
          }
      }
      return 1;
  }
  
  

  it gives output "no" for whatever i enter
• How to assign two or more values to a QMap Variable in Qt

  I am getting confused of how to store the values assigned from 3 different functions and storing them in a single map variable

  QMap<QString,QString> TrainMap = nullptr;   
  if(......)    
  (    
         TrainMap    =    PrevDayTrainMap();
         TrainMap    =    NextDayTrainMap();
         TrainMap    =    CurrentDayTrainMap();
  }
  

  The PrevDayTrainMap,NextDayTrainMap & CurrentDayTrainMap returns a set of values with Date and the TrainIdName.I need to store all the values from prevday,currentday and nextday in the TrainMap but it stores only the currentday values to the TrainMap as it is assigned at the last.I am not sure what to do so that it doesn't overwrite.If I should merge what is the way to do it?
• How to get pass an array through a function with a user input?

  I want to ask the user for the size of a 2D array arr[][], but also pass it through the function initializeArray. However, if I pass it through the function, I would have to have a size declarator for col, which doesn't allow the user to enter their own value for the size

    #include<iostream>
    using namespace std;
  
    void initializeArray(arr[][10], int N);
  
    int main() {
        int N;
        cout << "enter an array size: ";
        cin >> N;
        int arr[N][N];
  
        initializeArray(arr, N); // I get an error here
        for(int i = 0; i < N; i++) {
            for(int j = 0; j < N; j++)
                cout << arr[i][j] << " ";
            cout << endl;
        }
   }
  
    void initializeArray(int arr[][10], int N) {
        for(int i = 0; i < N; i++)
            for(int j = 0; j < N; j++)
                arr[i][j] = 0;
    }
  

  The only solution I found was the make arr[][] a global array, but in that case, I would have to still declare the size parameters, and I want the user to enter whatever they want. Is there another way to fix this?
• Two-dimensional array C++

  Problem: Write a program of a two dimensional integer array of exactly four rows and four columns, and find the sum of the integers each row of the array as well as determine the smallest inputted element/data in the array. The user will input the elements. Display the elements in tabular form. Make the program user friendly. Use a Class and a member function for the process involve.
• Pass Associative Array from Symfony Controller to Twig and JavaScript

  So, I have 2 arrays that I've combined into one array after making sure they're the same length as such.

  //Fetching Ratings for All Coaches & Making a Key, Value Associative Array with Coach id as Key and Rating as Value
          $coaches = $coachRepository->findAll();
          $rating = $coachRepository->findRatingByCoach();
          //Array of coach IDs
          $id_array = array();
          foreach ($coaches as $c){
              $id_array[] = $c->getId();
          }
          $combined = array_combine($id_array, $rating);
  

  Now I want to pass this key, value array to Twig template and JavaScript. I'm currently doing this

      return $this->render('...', [
          ..., 'combined'=>$combined
      ]);
  

  And I'm accessing the array in Twig as such

              {% for key, value in combined %}
                  {{ key }} - {{ value }}
              {% endfor %}
  

  And I'm getting this error.

  Object of class App\Entity\Coach could not be converted to string
  

  Looking at the Stack Trace I can see that the array combined is being passed in this form.

  'combined' => array(object(Coach))
  

  After a bit of debugging it turns out that I thought the issue was with the $id_array when in fact it's the $rating variable that's presenting an issue. I'm not sure why but I'm getting a single float value. I fixed the issue by changing how I'm fetching the $rating, now instead of using a QueryBuilder to get it from the DB, I'm getting it from list of Coaches as such

   //Array of coach IDs and array of Ratings
          $id_array = array();
          $rating_array = array();
          foreach ($coaches as $c){
              $id_array[] = $c->getId();
              $rating_array [] = $c->getRating();
          }
  

  Even if I set the array
• Sytax error: Missing ), but I don't see it. My quotation marks don't seem to be the problem either

  I've been working on this app script trying to automate data from a Google sheet to create events on Google Calendar. I've tried changing the Quotation marks from single to double and back. I've checked my () over and over. I cannot see what I've done that gives me the syntax error. If you can see it, please tell me. This is making me nuts.

  function AutomateCalendarEvent() {
    let sheet = SpreadsheetApp.getActiveSheet();
    let pqCalendar = CalendarApp.getCalendarById("zyxwvutsrqp");  
    let reservation = sheet.getRange("C2:E1105").getValues();
    reservation.splice(0, 1);
    let rows = sheet.getDataRange().getValues();
    rows.forEach(function (row, index)  {
      if (index === 0) return;
      if (row[C3]) return;
      
    pqCalendar.createAllDayEvent("Last Name"C2:C, "Arrival Date"D2:D, "Departure Date"E2:E);
      
     })
  }
  
• Why are there three program control structures? Not more or less?

  There are three program control structures. Sequence, selection, repetition structure. But why is there three? Not more or less? Or, are there more?