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一位老师在三张纸片上各写一个正整数,然后分别贴在三个学生的额头上．每个学生可以看见其他两人头上的数,而不知道自己头上的是什么数．老师说三个数中有一个数是另外两个数的和．老师问学生甲能否猜出自己头上的是什么数,甲回答说不能．问学生乙,乙也说不能．问学生丙,丙说猜出来了,自己头上的数是198．老师点头称是．请读者再猜:甲、乙头上的数是什么?
A teacher wrote a positive integer on each of the three sheets of paper, which were then placed on the forehead of each of the three students. Each student can see the numbers of the other two people, but they do not know what number is on their head. The teacher said that one of the three numbers is the sum of the other two numbers. The teacher asked student A whether he could guess what number was on his head. A answered that he could not. Ask student B, B also said not. Ask student C. C. guessed that the number on his head was 198. The teacher nodded and said yes. Ask the reader to guess again: What are the numbers on A and B?