c++, graphs, from adjacency matrix to incidence matrix, undirected graph

Question

c++, graphs, from adjacency matrix to incidence matrix, undirected graph

Please help me how to go from the adjacency matrix to the incidence matrix, I have already gone through everything and have not come to anything. I entered the adjacency matrix, maybe there are some ideas? And what is the general pattern between these two matrices?

#include "iostream"
#include "conio.h"
#include <stdlib.h>
    
using namespace std;
    
int main()
{
    int G[100][100], Vertex, Edge, x, y;
    cout << "Enter number of vertexes:";
    cin >> Vertex;
    cout << "\nEnter number of edges:";
    cin>> Edge;
    for(int i=1;i<=Vertex;i++)     // t.k matrica smejnosti eto -
        for(int j=1;j<=Vertex;j++) // bibarnaia n x n matrica
        {
            G[i][j]=0;     // prisvaivaem 0 elemantam matrici
        }
    cout << "\nEnter edges:\n " << endl;
    for(int i=1;i<=Edge;i++)
    {
        cout << "e1=" ;
        cin >> x;
        cout << "e2=";
        cin >> y;
        cout << endl;
        G[x][y]=1;
        G[y][x]=1;
    }
    cout << "\nAdjacency matrix:\n" << endl;
    for(int i=1;i<=Vertex;i++)
    {
        for(int j=1;j<=Vertex;j++)
        {
           cout << G[i][j] ;
        }
        cout << endl;
    }
    cout << endl;

    return 0;
    system("pause");
}

0

c++графы

Author: dIm0n, 2020-09-26

Source

1 answers

score 1 · Answer 1

Decision:

#include <iostream>

using namespace std;

int main()
{
    int vertexCount, edgeCount;
    cout << "Enter number of vertexes:";
    cin >> vertexCount;
    cout << "\nEnter number of edges:";
    cin>> edgeCount;

    auto matrix = new int*[edgeCount];
    for(auto i = 0; i < edgeCount; ++i){
        matrix[i] = new int[vertexCount];
    }

    cout << "\nEnter edges:\n " << endl;

    for(auto i = 0; i < edgeCount ; ++i)
    {
        int x,y = 0;
        cout << "e1=" ;
        cin >> x;
        cout << "e2=";
        cin >> y;
        cout << endl;
        matrix[x][y]=1;
        matrix[y][x]=1;
    }

    cout << "\nAdjacency matrix:\n" << endl;

    auto resultMatrix = new int*[edgeCount];
    for(auto i = 0; i < edgeCount; ++i){
        resultMatrix[i] = new int[vertexCount];
    }
    auto pointer = 0;

    for(auto i = 0; i < edgeCount; ++i) {
        for (auto j = i + 1; j < vertexCount; ++j) {
            if(matrix[i][j] == 1){
                resultMatrix[i][pointer]=1;
                resultMatrix[j][pointer]=1;
                ++pointer;
            }
        }
    }

    for(auto i = 0; i < edgeCount; ++i) {
        for (auto j = 0; j < vertexCount; ++j) {
            cout << resultMatrix[i][j] << " ";
        }
        cout << endl;
    }

    for(auto i = 0; i < vertexCount; ++i){
        delete[] matrix[i];
    }

    delete[] matrix;

    for(auto i = 0; i < vertexCount; ++i){
        delete[] resultMatrix[i];
    }

    delete[] resultMatrix;

    return 0;
}