docs: protected boolean[][] modifyDependencyMatrix(boolean M[][], double u, Random r) {
          //List<int[]> L = new ArrayList<int[]>();
          for (int j = 0; j < M.length; j++) {
              for (int k = j + 1; k < M[j].length; k++) {
                  if (/*
                           * !hasCycle(L) &&
                           */r.nextDouble() <= u) {
                      M[j][k] ^= true;
                      //L.add(new int[]{j,k});
                  }
              }
          }
          return M;
      }