public int ps(){
        int sp = Integer.parseInt(iw.get(2)[1].trim()), c = 0;
        List<Integer> col1 = new ArrayList<>();
        List<Integer> col2 = new ArrayList<>();
        for (int y = 0; y < Psize; y++) {
            if( (y+sp) >= Psize){
               for (int x = 0; x < Rsize; x++) {
                if (tt[x][y] != null) {
                List templist = (List) tt[x][y];
                    for (int j = 0; j < templist.size(); j++) {
                        col1.add((int) templist.get(j));
                    }
                }
                for(int y2=y+1; y2<Psize; y2++){
                    if (tt[x][y2] != null) {
                    List templist2 = (List) tt[x][y2];
                    for (int i = 0; i < templist2.size(); i++){
                            col2.add((int) templist2.get(i));
                    }
                    }
                }
               }
                for (int a = 0; a < col1.size(); a++) {
                for (int b = 0; b < col2.size(); b++) {
                    c += Integer.parseInt(aa.get(col1.get(a))[col2.get(b)].trim());
                }
                }
                col1.clear();
                col2.clear();
            }
            else{
                for (int x = 0; x < Rsize; x++) {
                    if (tt[x][y] != null) {
                        List templist = (List) tt[x][y];
                            for (int j = 0; j < templist.size(); j++) {
                                col1.add((int) templist.get(j));
                            }
                    }
                for(int y2=y+1; y2<(y+sp); y2++){
                    if (tt[x][y2] != null) {
                    List templist2 = (List) tt[x][y2];
                    for (int i = 0; i < templist2.size(); i++){
                        col2.add((int) templist2.get(i));
                    }
                    }
                }
                }
                for (int a = 0; a < col1.size(); a++) {
                for (int b = 0; b < col2.size(); b++) {
                    c += Integer.parseInt(aa.get(col1.get(a))[col2.get(b)].trim());

                }
                }
                col1.clear();
                col2.clear();
            }
        }
        System.out.println("Period Spread: "+c);
        return c;
    }