I've become good friends with several of the students in my school I met in theEnglish speech contest last year.
A. who
B. where
C. when
D. which
第1题:
I've _____ these lines again and again but I still keep forgetting them.
A. gone off
B. gone about
C. gone over
D. gone through
第2题:
下面程序输出的结果是( )。 #include<iostream> using namespace std; void main() { char ch[][8]={"good","better","best"}; for(int i=1;i<3;++i) { cout<<ch[i]<<endl; } }
A.good better
B.better best
C.good best
D.good
第3题:
第4题:
A. short
B. new
C. entire
D. good
第5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6题:
3. Good. I'll _________ (有空)then.