Program to check one graph is subgraph of another graph

#include<iostream>
using namespace std;

 int V1,V2,E1,E2;
 int **g1,**g2;
 
int main()
{
    int i,j,v1,v2;
 
 cout<<endl<<"\nEnter Vertices and Edges for the graph-1 :";
 cin>>V1>>E1;
 cout<<endl<<"\nEnter Vertices and Edges for the graph-2 :";
 cin>>V2>>E2;
 
 g1=new int*[V1];
 for(i=0;i<V1;i++)
 g1[i]=new int[V1];
 
 g2=new int*[V2];
 for(i=0;i<V2;i++)
 g2[i]=new int[V2];
 
 for(i=0;i<V1;i++)
  for(j=0;j<V1;j++)
   g1[i][j]=0;
 
 for(i=0;i<V2;i++)
  for(j=0;j<V2;j++)
    g2[i][j]=0;
 
 cout<<"\nEnter Graph-1 Details :"<<endl;
 for(i=0;i<E1;i++)
 {
  cout<<"Enter vertices for edge :"<<i+1<<" ";
  cin>>v1>>v2;
  g1[v1-1][v2-1]=1;
  g1[v2-1][v1-1]=1;
 }
 
 cout<<"\nEnter Graph-2 Details :"<<endl;
 for(i=0;i<E2;i++)
 {
  cout<<"Enter vertices for edge :"<<i+1<<" ";
  cin>>v1>>v2;
  g2[v1-1][v2-1]=1;
  g2[v2-1][v1-1]=1;
 }
 
 int k,l,found;
 for(i=0;i<=V1-V2;i++)
 {
  for(j=0;j<=V1-V2;j++)
  {
   k=0,l=0,found=1;
   for(k=0;k<V2;k++)
   {
    for(l=0;l<V2;l++)
    {
      if(g1[i+k][j+l]!=g2[k][l])
      {
       found=0;
       break;
      }
    }
    if(found==0)
    break;
   }
   if(k==V2&&l==V2)
   {
    found=1;
    break;
   }
  }
  if(found==1)
  break;
 }
 if(found==1)
 cout<<"\n\nGrapg g2 is subgraph of another graph g1"<<endl;
 else
 cout<<"\n\nGrapg g2 is not subgraph of another graph g1"<<endl;
 
 return 0;
}