return does not stop function, Recursive function issue? (programming exercise, Dynamic Programming, Levenshtein Back-trace)

Question

the printOptimalAlignment function is misbehaving. goto and return will not exit when the function reaches location (1,1)... where it should end, no crash and it stops at seemingly an arbitrary location of (6,6)... because for some reason it increments at the end of the function even though there is no increment-er for the values int yL, int xL, (but I don't follow why it calls itself if it gets to the end of the function without any "hits" on the if statements.

Full code: https://repl.it/@fulloutfool/Edit-Distance

void printOptimalAlignment(int** arr, string y, string x,int yL, int xL){
  int I_weight=1, D_weight=1, R_weight=1;
  bool printinfo_allot = 1,printinfo = 1; 

  if(printinfo_allot){
    cout<<"Location: "<<"("<<xL<<","<<yL<<")"<<"-------------------------------\n";
    cout<<"Same check Letters: "<<x[xL-2]<<","
      <<y[yL-2]<<"("<<(x[xL-2] == y[yL-2])<<")"<<"\n";
    cout<<"LL: "<<"("<<xL-1<<","<<yL<<")"
      <<":"<<arr[yL][xL-1]
      <<":"<<(arr[yL][xL-1]+I_weight)
      <<":"<<(arr[yL][xL])
      <<":"<<(((arr[yL][xL-1]+I_weight) == arr[yL][xL])==1)
      <<":"<<(yL>=1 && xL>=1)<<"\n";
    cout<<"xL state:"<<((&x[xL]))<<":"<<(x[xL-1])<<"\n";
    cout<<"yL state:"<<((&y[yL]))<<":"<<(y[yL-1])<<"\n";
    string tx = &x[xL];
    cout<<x.length()<<","<<(tx.length()+1)<<"\n";
  }

  string tx = &x[xL]; // slopy hotfix
  if(x.length()==(tx.length()+1)){
    cout<<"return functionality not working?-=-=-=-=-=-=-=-=\n";
    cout<<"-> Prep last, current distance = "<<arr[yL][xL] <<"\n";
    return;
    //printOptimalAlignment(arr,y,x,yL-1,xL-1);
    //cant use this goto... but where does it go?
    //goto because_Im_a_terrible_person;
    throw "how?... breaking rules... make it stop";
  }

  if(yL>=1 && xL>=1 && (x[xL-2] == y[yL-2]) == 1){
    if(printinfo){
      cout<<"-> Same (same char), current distance = "<<arr[yL][xL] <<"\n";
    }
    printOptimalAlignment(arr,y,x,yL-1,xL-1);
  }

  if(yL>=1 && xL>=1 && (arr[yL-1][xL-1] == arr[yL][xL])){
    if(printinfo){
      cout<<"-> Swap (same int), current distance = "<<arr[yL][xL] <<"\n";
      if(arr[yL-1][xL-1]==0)cout<<"---this is last---\n";
    }
    printOptimalAlignment(arr,y,x,yL-1,xL-1);
  }

  if(yL>0 && xL>0 && (arr[yL-1][xL]+D_weight == arr[yL][xL])){
    if(printinfo){
      cout<<"-> Delete, current distance = "<<arr[yL][xL]<<"\n";
    }
    printOptimalAlignment(arr,y,x,yL-1,xL);
  }

  //really weird ((yL>1 && xL>1) && (((arr[yL][xL-1]+I_weight) == arr[yL][xL])==1))
  //not true if it is?
  bool seperate = (((arr[yL][xL-1]+I_weight) == arr[yL][xL])==1);
  if(yL>=1 && xL>=1){
    if((((arr[yL][xL-1]+I_weight) == arr[yL][xL])==1) && (true)){
      if(printinfo){
        cout<<"-> Insert, current distance = "<<arr[yL][xL]<<"\n";
        cout<<"Next Location1: "<<"("<<xL-1<<","<<yL<<")"<<"\n";
      }
      printOptimalAlignment(arr,y,x,yL,xL-1);
      return;
      //how does it get here... also return gets ignored... prob another stack issue
      cout<<"insert function broke?????? @ (1,1) ???????????????\n";
      //return;

    }
  }
  return;
  cout<<"END... Hopefully.. if you see this Something went wrong\n";
  because_Im_a_terrible_person:
  cout<<"QUIT\n";
}

Answer 1

I suspect your problem is that your function calls itself and you don't appear to be taking into account what should happen next after that call to itself finishes. So you get to your finish condition where you say the return doesn't work, but it does... it just returns to where you left off in the previous call to printOptimalAlignment, which still might do something before returning to its caller, and so on. You have three different sites where you recursively call printOptimalAlignment that aren't immediately followed by a return statement, and at any of these it might be that the code will continue and trigger another of your conditional blocks.