C++ Programming Code Examples C++ > Computer Graphics Code Examples C++ Program to Represent Graph Using 2D Arrays C++ Program to Represent Graph Using 2D Arrays - This algorithm represents a graph using 2D arrays. - This method of representing graphs is not efficient. - The time complexity of this algorithm is O(v*v). - This algorithm takes the input of the number of vertex and edges. - Take the input of connected vertex pairs. - Print the graph using 2D arrays. - Exit. #include<iostream> #include<iomanip> using namespace std; // A function to print the matrix. void PrintMat(int **mat, int n) { int i, j; cout<<"\n\n"<<setw(4)<<""; for(i = 0; i < n; i++) cout<<setw(3)<<"("<<i+1<<")"; cout<<"\n\n"; // Print 1 if the corresponding vertexes are connected otherwise 0. for(i = 0; i < n; i++) { cout<<setw(3)<<"("<<i+1<<")"; for(j = 0; j < n; j++) { cout<<setw(4)<<mat[i][j]; } cout<<"\n\n"; } } int main() { int i, v, e, j, v1, v2; // take the input of the number of edges. cout<<"Enter the number of vertexes of the graph: "; cin>>v; // Dynamically declare graph. int **graph; graph = new int*[v]; for(i = 0; i < v; i++) { graph[i] = new int[v]; for(j = 0; j < v; j++)graph[i][j] = 0; } cout<<"\nEnter the number of edges of the graph: "; cin>>e; // Take the input of the adjacent vertex pairs of the given graph. for(i = 0; i < e; i++) { cout<<"\nEnter the vertex pair for edge "<<i+1; cout<<"\nV(1): "; cin>>v1; cout<<"V(2): "; cin>>v2; graph[v1-1][v2-1] = 1; graph[v2-1][v1-1] = 1; } // Print the 2D array representation of the graph. PrintMat(graph, v); }