Chapter 3 narrates the horrific events that occur when Elie and his father arrive at Auschwitz and begin to learn the true reality of what is happening to them and how they are to be treated. Certainly the shock of how they are degraded and treated like animals is matched by the joy of survival as they realise that they are alive, at least for the present. As the description of their activities continues, Elie answers your question for you in a way that highlights the menotony of their routine:
Days went by. In the mornings: black coffee. At midday; soup. By the third day, I was eagerly eating any kind of soup... At six o'clock in the afternoon: roll call. Followed by bread with something. At nine o'clock: bedtime.
Note how the brief nature of the sentences reinforces the sense of how this routine came to dominate Elie and the prisoners' lives - this short routine becomes their entire life as their life's purpose shrinks to the importance of getting through each day and surviving.