Three models for the formation of 10 planets. Top: formation of 10 independent planets (each of them growing in an identical disc). Middle: the competition for gas and solid accretion, as well as the excitation of planetesimals by all planets, is taken into account. The gravitational interactions between planets are not included. The cross indicates an ejected planet, the big dots indicate collision between planets. Bottom: full model, including the competition for gas and solid accretion, the excitation of planetesimals by all planets, and the gravitational interactions between planets.