前辈们晚上好，一般我们都可以用算法生成笛卡尔集，但是如果现在有一个笛卡尔集，要让起反向生成，变成元数据的话，请问各位前辈们可否指导一下。
ringa_lee
Suppose the Cartesian set C {(a, b) | a belongs to A, b belongs to B} comes from A x B , then traverse each element in C and add the element a to the set X and b to the set Y . Then the final X and Y are the original two sets A and B.
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Suppose the Cartesian set C {(a, b) | a belongs to A, b belongs to B} comes from A x B , then traverse each element in C and add the element a to the set X and b to the set Y . Then the final X and Y are the original two sets A and B.