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Working with compilers for errors-Adjacency matrix

closed account Sz6592yv (64)
Errors:
So I have errors that I need help fixing for c++11. This deals with undirected graph in the format of adjacency matrix.
prompt:
Write a C++ 11 function named is_connected() to determine whether an undirected unweighted graph is connected when the graph is stored in the adjacency matrix format.
Write a main program that hard-codes the entries of the adjacency matrix and then passes the matrix to the is_connected function. Every graph has vertices labeled with consecutive unsigned integers starting at 0.
So I have those done already, and I need help with these compiler issues that make no sense. One of them is I already included the packages for them
Errors:
In file included from lin_0912.cpp:7:0:
lin_0912.h: In function ‘bool is_connected(Matrix&)’:
lin_0912.h:129:6: error: ‘vector’ was not declared in this scope
vector< bool >reached(graph.size(),false);
^
lin_0912.h:129:6: note: suggested alternative:
In file included from /usr/include/c++/4.8/vector:64:0,
from lin_0912.cpp:4:
/usr/include/c++/4.8/bits/stl_vector.h:210:11: note: ‘std::vector’
class vector : protected _Vector_base<_Tp, _Alloc>
^
In file included from lin_0912.cpp:7:0:
lin_0912.h:129:14: error: expected primary-expression before ‘bool’
vector< bool >reached(graph.size(),false);
^
lin_0912.h:129:14: error: expected ‘;’ before ‘bool’
lin_0912.h:130:7: error: ‘queue’ was not declared in this scope
queue< uint8_t > to_be_explored;
^
lin_0912.h:130:7: note: suggested alternative:
In file included from /usr/include/c++/4.8/queue:64:0,
from lin_0912.cpp:5:
/usr/include/c++/4.8/bits/stl_queue.h:93:11: note: ‘std::queue’
class queue
^
In file included from lin_0912.cpp:7:0:
lin_0912.h:130:22: error: expected primary-expression before ‘>’ token
queue< uint8_t > to_be_explored;
^
lin_0912.h:130:24: error: ‘to_be_explored’ was not declared in this scope
queue< uint8_t > to_be_explored;
^
lin_0912.h:137:9: error: ‘reached’ was not declared in this scope
reached.at(current_node)=true;
^
lin_0912.h:146:19: error: ‘reached’ was not declared in this scope
return find(reached.begin(), reached.end(), false) == reached.end();
^
lin_0912.h:146:56: error: ‘find’ was not declared in this scope
return find(reached.begin(), reached.end(), false) == reached.end();
^
lin_0912.h:146:56: note: suggested alternative:
In file included from /usr/include/c++/4.8/algorithm:62:0,
from lin_0912.h:9,
from lin_0912.cpp:7:
/usr/include/c++/4.8/bits/stl_algo.h:4432:5: note: ‘std::find’
find(_InputIterator __first, _InputIterator __last,
^
lin_0912.cpp: In function ‘int main()’:
lin_0912.cpp:23:28: error: invalid initialization of reference of type ‘Matrix&’ from expression of type ‘Matrix’
cout< ^
In file included from lin_0912.cpp:7:0:
lin_0912.h:126:9: error: in passing argument 1 of ‘bool is_connected(Matrix&)’
bool is_connected(Matrix & graph)
^
lin_0912.h: In function ‘bool is_connected(Matrix&)’:
lin_0912.h:147:4: warning: control reaches end of non-void function [-Wreturn-type]
}

.cpp:
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#include <cstdint>
#include <vector>
#include <queue>
#include <iostream>
#include "lin_0912.h"
using namespace std;

int main()
{
   Matrix <bool> graph(6,6);
   
   
   graph.at(0, 1)=true;
   graph.at(0,2)=true;
   graph.at(2,0)=true;
   graph.at(2,1)=true; 
   graph.at(3,4)=true;
   graph.at(3,5)=true;
   graph.at(4,3)=true;
   graph.at(5,3)=true;
   cout<<is_connected(graph)<<endl;
   return 0;
}

.h:
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#ifndef MATRIX_H
#define MATRIX_H

#include <cassert>

#include <cstdint>
#include <queue>
#include <vector>
#include <algorithm>
/**
 * A generic 2-dimensional array class
 * @author Jon Beck
 * @version 8 September 2017
 */
template <class Object>
class Matrix
{
 public:
  /**
   * Constructor, specifying number of both rows and columns
   * @param rows the number of rows
   * @param cols the number of columns
   */
  Matrix( uint16_t rows, uint16_t cols );

  /**
   * Access to an element to allow modification
   * @param row the row index
   * @param col the column index
   * @return reference to the element at that position
   */
  Object & at( uint16_t row, uint16_t col );

  /**
   * Constant access to an element
   * @param row the row index
   * @param col the column index
   * @return constant reference to the element at that position
   */
  const Object & at( uint16_t row, uint16_t col ) const;

  /**
   * Destructor to free allocated memory
   */
  ~Matrix();

  /**
   * Copy constructor to make 1-1 copy of existing matrix
   * @param m the existing matrix to be copied
   */
  Matrix( const Matrix<Object> & m ); // Copy constructor

  /**
   * Disallow the rvalue copy constructor
   */
  Matrix( const Matrix<Object> && m ) = delete;

  /**
   * Assignment operator to make 1-1 copy of existing matrix
   * @param m the existing matrix to be copied
   */
  Matrix & operator= ( const Matrix<Object> & m ); // Assignment operator

  /**
   * Disallow the rvalue assignment operator
   */
  Matrix & operator= ( const Matrix<Object> && m ) = delete;

  /**
   * Accessor to determine how many rows are in the matrix
   * @return the number of rows in the matrix
   */
  uint16_t numrows() const;

  /**
   * Accessor to determine how many columns are in the matrix
   * @return the number of columns in the matrix
   */
  uint16_t numcols() const;

 private:
  uint16_t rows;
  uint16_t cols;
  Object* data;
};

template <class Object>
Matrix<Object>::Matrix( uint16_t rows, uint16_t cols )
: rows( rows ), cols( cols )
{
  data = new Object[ rows * cols ];
}

template <class Object>
Matrix<Object>::~Matrix()
{
  delete[] data;
}

template <class Object>
Object & Matrix<Object>::at( uint16_t row, uint16_t col )
{
  assert( row < rows && col < cols );
  return data[ cols * row + col ];
}

template <class Object>
const Object & Matrix<Object>::at( uint16_t row, uint16_t col ) const
{
  assert( row < rows && col < cols );
  return data[ cols * row + col ];
}

template <class Object>
uint16_t Matrix<Object>::numrows() const
{
  return rows;
}

template <class Object>
uint16_t Matrix<Object>::numcols() const
{
  return cols;
}

   bool is_connected(Matrix<uint8_t> & graph)
   {
    
     vector< bool >reached(graph.size(),false);
      queue< uint8_t > to_be_explored; 
      to_be_explored.push(0);

     while(!to_be_explored.empty())
      {
        uint8_t current_node=to_be_explored.front();
        to_be_explored.pop();
        reached.at(current_node)=true;
        for(uint8_t adjacent=0; adjacent<graph.numcols(); ++adjacent)
        {
           if(!reached.at(adjacent) && graph.at(current_node, adjacent))
           {
              to_be_explored.push(adjacent);
           } 
        }
      }
      return find(reached.begin(), reached.end(), false) == reached.end();
   }
   

#endif
Last edited on
Enoizat (1343)
<Secret name>.h:
line 129-130:
1
2
 
std::vector< bool >reached(graph.size(), false); // must be std::vector
std::queue< uint8_t > to_be_explored; // must be std::queue


Again, line 129:
vector< bool >reached(graph.size(), false);
Where do you define Matrix::size()?

Line 62:
Matrix & operator= ( const Matrix<Object> & m ); // Assignment operator
You declare a non defaulted version of overloaded operator=. Where do you define it?
closed account Sz6592yv (64)
Ok So I needed to just ad using namespace std; in header file.

remaining errors:
In file included from lin_0912.cpp:7:0:
lin_0912.h: In function ‘bool is_connected(Matrix<unsigned char>&)’:
lin_0912.h:130:34: error: ‘class Matrix<unsigned char>’ has no member named ‘size’
vector< bool >reached(graph.size(),false);
^
lin_0912.cpp: In function ‘int main()’:
lin_0912.cpp:23:28: error: invalid initialization of reference of type ‘Matrix<unsigned char>&’ from expression of type ‘Matrix<bool>’
cout<<is_connected(graph)<<endl;
^
In file included from lin_0912.cpp:7:0:
lin_0912.h:127:9: error: in passing argument 1 of ‘bool is_connected(Matrix<unsigned char>&)’
Last edited on
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