 # C++ Programming Code Examples

## C++ > Computer Graphics Code Examples

### Program to Describe the Representation of Graph using Adjacency List

``` Program to Describe the Representation of Graph using Adjacency List - This algorithm represents a graph using adjacency list. - This method of representing graphs is not efficient. - The time complexity of this algorithm is O(v*e). - This algorithm takes the input of the number of vertex and edges. - Take the input of connected vertex pairs. - Print the adjacency list. - Exit. #include<iostream> using namespace std; int main() { int i, v, e, j, count; // take the input of the number of vertex and edges. cout<<"Enter the number of vertexes of the graph: "; cin>>v; cout<<"\nEnter the number of edges of the graph: "; cin>>e; int edge[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>>edge[i]; cout<<"V(2): "; cin>>edge[i]; } // Print the adjacency list representation of the graph. cout<<"\n\nThe adjacency list representation for the given graph: "; for(i = 0; i < v; i++) { count = 0; // For each vertex print, its adjacent vertex. cout<<"\n\t"<<i+1<<"-> { "; for(j = 0; j < e; j++) { if(edge[j] == i+1) { cout<<edge[j]<<" "; count++; } else if(edge[j] == i+1) { cout<<edge[j]<<" "; count++; } else if(j == e-1 && count == 0) cout<<"Isolated Vertex!"; } cout<<" }"; } } ``` 