Microsoft bridge problem and testing personnel literacyLinks to related articles are as follows:
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1.1.1 Microsoft bridge problem and testing personnel literacyMicrosoft's questions about crossing the bridge have almost become a well-known issue in the IT industry. The problem is as follows: four people spend a small bridge in the evening and need to use a flashlight when crossing the bridge. There is only one flashlight, each time, only two people can pass the bridge at most (when the bridge cannot be supported, the bridge will collapse). The speed of four people crossing the bridge is 1 minute, 2 minutes, 5 minutes, and 10 minutes, respectively, how long does it take at least 4 people to go through Xiaoqiao? The average person may be right away thinking about how to arrange the order of the four people crossing the bridge to minimize the bridge time. A slightly intelligent person may come up with the answer: "Let's let 1, 2 go, 1 go back, 5, 10 go back, 2 go back, 1, 2 go back." It takes 17 minutes to let 4 people go. Of course, if the mathematical knowledge is good enough, we may use graph theory to analyze this problem. Finally, we find that this is a shortest path algorithm problem in graph theory. We only need to create a Directed Graph Based on the bridge status, then, find the shortest path to obtain the bridge plan with the minimum time. (If you are interested in solving this problem using graph theory, read another article on Graph Theory solutions for Microsoft bridge problems in my blog ). Now, if a tester is asked to answer this question, is it okay to answer the question just like above? If you can answer questions in a short time, it means that you are smart, but what you need as a tester is not a simple result, but a comprehensive analysis of the problem, only the answer with the shortest time of 17 minutes cannot meet the requirements of the tester. As a tester, you must first ask many unknown factors in the question. The following questions may be what the tester wants to know: Why should n these four spend the night on this bridge, are they on their way home, on a wild adventure, lost or attacked? If they were attacked, would there be two people who ran away alone and couldn't come back to pick up the remaining two? N why is the gap between the four people crossing the bridge so large that the maximum and minimum time difference is 10 times? Then I can ask, what are the four people? What are their ages? Do they have people with disabilities or children? If there is a child or a disabled person, can the child and the disabled person not cross the bridge at the same time? (That is to say, 5 and 10 cannot cross the bridge at the same time.) n since only two people can cross the bridge at the same time, what is the maximum load-bearing capacity of the bridge? Can two heaviest people cross the bridge at the same time? N is the flashlight okay? Is the power in the flashlight used up? Or how long can the power of the flashlight be used? Or will the flashlight fall under the bridge or break down? N what was the weather at that time? Whether there is wind or rain, thunder or blizzard, will someone be affected by the wind or thunder when crossing the bridge. Or when the weather goes bad, they need to spend more time crossing the bridge. N what is the temperature at that time? If the temperature is lower than 0 degrees, whether the bridge is frozen or not. N is there a rescue engineer on the opposite side of the bridge? For example, 1 and 2 may have met the rescue engineer on the opposite side. 1 may have taken the rescue engineer's notebook to pick up the remaining two people, it takes at least 14 minutes to bridge the bridge. N is there a flood or a sudden rise in water that will overwhelm the Bridge during the bridge? N will there be factors such as beeching and other factors affecting the speed of the bridge? N what is under the bridge? Is it Water Creek, water-free gully, or a deep Cliff? Can someone climb up after they fall down? There are no other shortcuts next to bridge n. Can a person of n 1 minute carry a person of 10 minutes to cross the bridge? If so, how long does it take? How long is bridge n? How far can a flashlight be taken? Do people in the past can use a flashlight at the other end of the bridge to illuminate the bridge for people in the past to bridge the bridge? The determination of these problems will affect the shortest time required for crossing the bridge. In different situations, the shortest time required for crossing the bridge is different. The above is just a few questions, and more questions can be explored by the readers themselves. If more than two new questions can be found on the basis of the above, so I believe that you have the testing staff to fully analyze the problem. However, even if you cannot find new problems, and many of the above problems do not come to mind, it does not matter, after learning the test case design method in Chapter 2, you may be pleasantly surprised to find that you have the ability to discover many new problems. Of course, beginners may think that some problems seem to be at the top of the list, but as a tester, what they want is the spirit of getting started.
