32. —Shall I tell Bob the news?
—No,you _________.I've told him already.
A. shouldn’t
B. wouldn’t
C. mustn’t
D. needn't
第1题:
A)ashouldn't eat
B)mustn't have eaten
C)shouldn't have eaten
D)mustn't eat
第2题:
Jerry: I've been back from a business trip.
Bob: ______
A、It's very nice of you.
B、How's everything going?
C、You're kind to say so.
D、I'd love to.
第3题:
B 宽度优先(种子染色法)
5.关键路径
几个定义: 顶点1为源点,n为汇点。
a. 顶点事件最早发生时间Ve[j], Ve [j] = max{ Ve [j] + w[I,j] },其中Ve (1) = 0;
b. 顶点事件最晚发生时间 Vl[j], Vl [j] = min{ Vl[j] – w[I,j] },其中 Vl(n) = Ve(n);
c. 边活动最早开始时间 Ee[I], 若边I由<j,k>表示,则Ee[I] = Ve[j];
d. 边活动最晚开始时间 El[I], 若边I由<j,k>表示,则El[I] = Vl[k] – w[j,k];
若 Ee[j] = El[j] ,则活动j为关键活动,由关键活动组成的路径为关键路径。
求解方法:
a. 从源点起topsort,判断是否有回路并计算Ve;
第4题:
Ted: How are you, Bob ?
Bob: _____________.
A、How are you?
B、I'm fine.Thank you.
C、How do you do?
D、Nice to meet you.
第5题:
A. would have seen
B. would see
C. have seen
D. saw