1000011011100000100000111000011110000000110000001 1 2 3 4 5 6 71234567M =SiA(Si)C (Si)R(Si)表4-1 可达集、先行集、共同集和起始集例表OO1110110011110010011101111 3 4 5 6 1 2 7 3456127M(P)=P1P2表4-2 级位划分过程表1110110011111011101110001 5 4 6 3 1 2 7 5463127M(L)=L1L2L3L1L2L3001110110011110110015 4 3 1 2 7 543127M(L)=L1L2L3L1L2L300110011001110011001 5 4 3 1 2 7 543127M(L)=L1L2L3L1L2L300010001000010001001 5 4 3 1 2 7 543127A=M(L)- I =L1L2L3L1L2L300S1S2S7S3S4S5S6第1级第2级第3级区域划分级位划分强连接要素缩减剔出超级关系去掉自身关系绘图(块三角)(区域块三角)(区域下三角)结束5162374图4-5 例 4-1 有向图返回