1. A is a matrix of m*n, and B is a matrix of n*m, so now there is (AB)x=0, discuss the situation of m, n and solution x (non-zero solution, no solution)
2.a is the eigenvector of A, then what is the eigenvector of (PAP^(-1))
3. Cattle eat grass (28 cattle for 9 days, 25 cattle for 12 days, 22 cattle for a few days, the answer may be 18 days)
4. int func(int* nums, int N, int S), a positive element array nums, add a sign to it to make the sum S, and return the total number of ways to sign (programming question)
5. What are the edge detection operators (image science)
7. There is a box of table tennis balls, of which six are new and two are old. First play a match to take two of them, put them back and play another match to take two. May I ask the probability that two of them are new balls in the last match What is it (the answer is 225/(28*28)=0.287)
8. There is a point in space, which is translated by one bit in the positive direction of the x-axis, and then rotated 60 degrees counterclockwise. What is its transformation matrix?
9. There is a building. At the beginning, each person will input the number of floors they are on. Then which floor will the elevator stop at, so that the sum of the costs spent by personnel on each floor is the smallest. Please write your optimization function (min{∑ (ni-x)*i}, where ni is the number of people going downstairs on the i floor, and x is the number of target floors)
10. Affine transformation, which property may change (the answer is area)
11. Which of the following formats (such as RGB) is most comfortable for human vision
12. Fourier transform, perform Fourier transform on m*n image, F(u, v) is its Fourier function, now what is the Fourier transform at (0,0) point
13. There are cats and dogs in the picture, which neural network to use (answer convolution cnn)
14. Which of the following is not a target detection model, only remember the FCNN and ALEXNET options among the four options
15. The linked list outputs the kth element from the bottom (programming question)
There are also C++ addresses, references, and const assignment legality (for example, assignments are made when const is initialized, and cannot be changed after assignments)