1. There are 5 departments of football teams in a college that need to play round-robin matches, that is, there is a match between every two teams. The winner of each game gets 2 points, the loser gets 0 points, and the two teams each get 1 point in a tie. The final results of the competition each department football team score different from each other, are known:
(1) the first team not too flat
(2) second team had no negative
(3) no better than fourth-place team
so , May I have a tie for all matches ()
A.4
B.5
C.6
D.7
2. Randomly arrange 1, 2, 3, 4, 5, 6 and mark them as a, b, c, d, e, f, the probability that the sum of two three-digit numbers abc + def is even is ()
A .0.4
B.0.5
C.0.6
D.0.9
3. The following statement is correct ()
A. The average time complexity of the red-black tree insertion operation is o(log n), and the worst time complexity is o(n*log n)
B. The best case of merge sort is complicated Degree o(log n)
C. Worst-case complexity of heap sorting o(n^2)
D. No matter whether the linear table adopts sequential storage structure or chain storage structure, the time complexity of deleting the node with value x is o (n)
4. The advantages of using a linked list to represent a linear table are ()
A. It is convenient for random access
B. It is convenient for insertion and deletion
C. It takes less storage space than a sequential table
D. The physical order of the data elements is the same as the logical order
5.若 3 s i n 3 x + c o s 3 x 3sin^3x + cos^3x 3 s i n3 x+cos3 x= 3, thensin 2021 x + cos 2021 x sin^{2021}x + cos^{2021}xyes i n2021x+cos2 0 2 1 xvalue ()
A.0.5
B.1
C.2
D.2021
6. A sequence is {10,12,19,20,29,41,50,55,76,90,100}, using the dichotomy to find the keyword 12 requires () comparisons.
A.1
B.2
C.3
D.4
7. Let a, b, c, d be real numbers, find a 2 + b 2 + c 2 + d 2 + ab + ac + ad + bc + bd + cd + a + b + c + da^2+b^ 2+c^2+d^2+ab+ac+ad+bc+bd+cd+a+b+c+da2+b2+c2+d2+a b+ac+ad+bc+bd+cd+a+b+c+The minimum value of d is ()
A.0
B.-1
C.-1/2
D.-2/5
8. The number of different binary trees whose preorder sequence is a, b, c, d, e is ()
A.39
B.40
C.41
D.42
9. The following () is the common point of the greedy algorithm and the dynamic programming algorithm.
A. Overlapping subproblems
B. Constructing the optimal solution
C. Greedy selection property
D. Optimal substructure property
10. In the union search problem, it is known that the set elements 0~8, so the corresponding parent node numbers are {1,-4,1,1,-3,4,4,8,-2} (Note: -n represents the tree root and the corresponding set size is n), then after the set where elements 3 and 8 are merged (requires that the small set must be merged into the large set), the corresponding tree root and parent node number values of the set are ( )
A.1 and -6
B.8 and -5
C.8 and -6
D.4 and -5
11. A Huffman tree has a total of 215 nodes, and Huffman coding is performed on it, and the function obtains () different code words
A.107
B.108
C.214
D.215
12. Euler graph G refers to a graph that can form a closed loop, and each edge of graph G happens to appear on this closed loop once (that is, drawn by one stroke). In the following descriptions, it is not necessarily Euler's graph ()
A. A graph containing Euler's orbit (Euler's orbit refers to a closed path that passes through each side of the graph exactly once)
B. It contains Euler's closed trace (Eulerian closed trace refers to the path that passes through each side of the graph exactly once)
C. There is a loop that passes through each vertex exactly once
D. The graph itself is a closed trace
E. There is no vertex with an odd degree in graph G
13. An air force base has this type of aircraft: the aircraft has only one fuel tank, and the same type can refuel each other, and a full tank of fuel can supply an aircraft to fly half a circle around the earth. Among them: all bases can only take off from this base, and must return to the base safely, and are not allowed to fall midway, and there is no airport in between. If at least one aircraft can circumnavigate the earth and return to the air base at the time of takeoff, at least this type of aircraft must be dispatched ()
A.5
B.6
C.8
D.15
14. If the calculation time of a certain algorithm is expressed as a grounding relation: T(N)=2T(N/2)+NlogN, T(1)=1. Then the time complexity of the algorithm is ()
AO(N)
BO(NlogN)
CO(N log2N)
DO(N2)
15. The input sequence of a certain stack is a, b, c, d, in the following four sequences, it is impossible to be the output sequence ()
Aa, c, b, d
Bb, c, d, a
Cc, d,b,a
Dd,c,b,a
16. For a two-dimensional array A[4,4] with an element size of 32, after reading A[1,1], reading () elements must be the fastest
AA[1,0]
BA[1 ,2]
CA[0,1]
DA[2,1]
17. Regarding the storage engine of Mysql, the difference between MyISAM and InnoDB, the following statement is correct ()
A. MyISAM row lock, there will be deadlock
B. MyISAM is suitable for applications with frequent insert and update operations
C. InnoDB support Foreign key
D.InnoDB supports full-text index
18. The sequential storage scheme of a complete binary tree refers to storing the nodes of a complete binary tree from top to bottom, from left to right, into an array of sequential structure at a time. Assuming that the root node is stored at position 1 of the array, the kth If the parent node of the node number exists, it should be stored in the number position () in the array
A.2k
B.2k+1
Ck/2 (rounded down)
D.(k+1)/2 (rounded down)
19. In the OSI reference model, ensuring end-to-end reliability is done at the () level
A. Data link layer
B. Network layer
C. Transport layer
D. Session layer
20. Regarding deadlock, which one of the following statements is wrong ()
A. Deadlock is a state where two or more processes are blocked indefinitely and wait for each other
B. Circular waiting is a sufficient condition for deadlock
C. Deadlock Lock processing strategy, ostrich strategy, prevention strategy, avoidance strategy, detection and recovery strategy
D. The cause of deadlock is competition for resources and illegal process advancement sequence