// Given a string and a non - empty substring sub, compute recursively the largest substring which starts and ends with sub and return its length.
int strDist( string str, string sub )
{
if( str.length() < sub.length() )
return 0;
if( str.substr( str.length() - sub.length(), sub.length() ) == sub )
return str.length() - str.find( sub, 0 );
return strDist( str.substr( 0, str.length() - 1 ), sub );
}
vector<vector<neighbor> > generateGraph(vector<string> &strVec) {
auto n = strVec.size();
// the graph is saved by an adjacency list
vector<vector<neighbor> > adjList(n, vector<neighbor>());
if(strVec.size() == 0)
return adjList;
for(int i=0; i<n-1; i++) {
for(int j=i+1; j<n; j++) {
if(strDist(strVec[i], strVec[j]) == 1) {
adjList[i].push_back(neighbor(j, 1));
adjList[j].push_back(neighbor(i, 1));
}
}
}
return adjList;
}