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Mathematical position problem
According to the meaning of the question, Beibei can only stand at both ends of a row of five positions, so for Beibei, there are only two positions to stand. After Beibei occupied one position, the rest included four positions in the middle position, but Nini did not stand in the middle. For Nini, she has only three positions to choose from, that is to say, she has only three ranking methods. After Nini stood up, there were still three places left. If Jingjing stands first, she also has three options to choose her position. Jingjing stood well and left two positions. Huanhuan or Yingying only chose two positions at first, and the remaining position can only be the last one. In this way, Beibei stood in two directions, Nini stood in three directions, Nini stood in three directions, Huanhuan and Yingying stood in two directions. A * * * can be arranged in 2×3×3×2=36 ways, that is, 36 different photos can be taken.

The problem is that Beibei must not stand at both ends and can only change three positions. After occupying a position, Beibei includes four positions in the middle, and Nini can't stand in the middle, but can only occupy three positions. After Beibei and Nini stand, three people can stand at will, that is, one of the three people has three choices, and the other two have only two choices, so the whole arrangement is 3 × 3× 3 × 2 =.