message: Rewrite index shift
diff: @@ -397,12 +397,7 @@ void AdamsBashforthSolver::Step(Vector &x, double &t, double &dt)
  t += dt;
  // Shift the index
  - int tmp = idx[smax-1];
  - for (int i = smax-1; i > 0; i--)
  - {
  - idx[i] = idx[i-1];
  - }
  - idx[0] = tmp;
  + for (int i = 0; i < smax; i++) idx[i] = (smax + idx[i] - 1)%smax;
  }
  const double AB1Solver::a[] =
  @@ -472,12 +467,8 @@ void AdamsMoultonSolver::Step(Vector &x, double &t, double &dt)
  t += dt;
  // Shift the index
  - int tmp = idx[smax-1];
  - for (int i = smax-1; i > 0; i--)
  - {
  - idx[i] = idx[i-1];
  - }
  - idx[0] = tmp;
  + for (int i = 0; i < smax; i++) idx[i] = (smax + idx[i] - 1)%smax;
  +
  }
  const double AM0Solver::a[] =
  