GraphMatrix

#include <iostream>
using namespace std;


int main() {
    int v, row, column, c;
    cout << "Number of Vertices: ";
    cin >> v;

    int mat[v][v];
    for (int i = 0; i < v; i++)
        for (int j = 0; j < v; j++)
            mat[i][j] = 0;


    cout << "Enter the Edges" << endl;
    cout << "Enter 0 0 to end" << endl;
    int edge = 1;
    do {
        cout << "Edge " << edge << ": ";
        cin >> row >> column;
        if (row > 0 && row < v && column  > 0 && column < v) {
            mat[row - 1][column - 1] = 1;
            mat[column - 1][row - 1] = 1;
            edge++;
        }
        else if (row != 0 || column != 0)
            cout << "Invalid Input" << endl;
    } while (row != 0 && column != 0);

    //printing the matrix
    for (int i = 0; i < v; i++) {
        for (int j = 0; j < v; j++)
            cout << mat[i][j] << " ";
        cout << endl;
    }
    cout << endl;

    //ODD degree
    int odds = 0;
    cout << "Vertices with Odd Degree: ";
    for (int i = 0; i < v; i++) {
        c = 0;
        for (int j = 0; j < v; j++)
            if (mat[i][j] != 0)
                c++;
        if (c % 2 != 0) {
            odds++;
            cout << i + 1 << " ";
        }
    }
    cout << endl;
    cout << "Number of Vertices with Odd Degree: " << odds << endl << endl;

    //Degree 3
    int deg3 = 0;
    cout << "Vertices with Degree 3: ";
    for (int i = 0; i < v; i++) {
        c = 0;
        for (int j = 0; j < v; j++)
            if (mat[i][j] != 0)
                c++;
        if (c == 3) {
            deg3++;
            cout << i + 1 << " ";
        }
    }
    cout << endl;
    cout << "Number of Vertices with Degree 3: " << deg3 << endl << endl;

    //Max Degree
    int maX = 0;
    for (int i = 0; i < v; i++) {
        c = 0;
        for (int j = 0; j < v; j++)
            if (mat[i][j] != 0)
                c++;
        if (c > maX)
            maX = c;
    }
    cout << "Maximum Degree is: " << maX << endl;
    cout << "Vertices with (Maximum) Degree (" << maX << "): ";
    for (int i = 0; i < v; i++) {
        c = 0;
        for (int j = 0; j < v; j++)
            if (mat[i][j] != 0)
                c++;
        if (c == maX)
            cout << i + 1 << " ";
    }
    cout << endl << endl;

    return 0;
}