Kamishirasawa Keine always says, "If you don't know what to do, why not give mathematical practice a try." However, Cirno is way too much talented to work on simple problems. Therefore, you are now tasked to crack one. We consider one operation on a set Sas selecting msubsets ofSin order . Now you need to figure out how many possible operations that the mselected subsets are pairwise disjoint. As the answer may get very large, you need to print the answer after modulo 998244353.
Kamishirasawa Keine always says, "If you don't know what to do, why not give mathematical practice a try." However, Cirno is way too much talented to work on simple problems. Therefore, you are now tasked to crack one. We consider one operation on a set S as selecting m subsets of S in order (You can select the same subset multiple times and the selected subset can be empty). Now you need to figure out how many possible operations that the m selected subsets are pairwise disjoint. As the answer may get very large, you need to print the answer after modulo 998244353.
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