3SUM

In computational complexity theory, the 3SUM problem asks if a given set of  real numbers contains three elements that sum to zero. A generalized version, k-SUM, asks the same question on k numbers. 3SUM can be easily solved in  time, and matching  lower bounds are known in some specialized models of computation.


In computational complexity theory, the 3SUM problem asks if a given set of real numbers contains three elements that sum to zero. A generalized version, k-SUM, asks the same question on k numbers. 3SUM can be easily solved in time, and matching lower bounds are known in some specialized models of computation.
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