实现操作系统同步与互斥，爸爸，儿子和女儿间的放水果吃水果问题，利用PV操作实现功能-Its operation system, dad, synchronization and sons and daughters of fruit, fruit put by PV operation function

fruit recongnize is importart understand the code beefore of play

经典问题 吃水果问题 使用信号量解决进程同步(classical question fruit eating)