Purpose of inherit and derivation Purpose of inherit: Realizing code reused. Purpose of derivation: When a new problem appears and the original program can't resolve it,we must reconstruct the original program. 2017年4月26日星期 第11章继承与派生 6 0雪2时16分23秒 BACK NEXTHOME2017年4月26日星期 三12时16分23秒 第11章 继承与派生 6 • Purpose of inherit: Realizing code reused. • Purpose of derivation: When a new problem appears and the original program can’t resolve it, we must reconstruct the original program