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RU-ALLRUSSIAN 1982 Problem 11

    a1,a2,…,a1982\mathrm{a}_1, \mathrm{a}_2, \ldots , \mathrm{a}_{1982} is a permutation of 1, 2, ..., 1982. If a1>a2\mathrm{a}_1 > \mathrm{a}_2 , we swap a1\mathrm{a}_1 and a2\mathrm{a}_2 . Then if (the new) a2>a3\mathrm{a}_2 > \mathrm{a}_3 we swap a2\mathrm{a}_2 and a3\mathrm{a}_3 . And so on. After 1981 potential swaps we have a new permutation b1,b2,…,b1982\mathrm{b}_1, \mathrm{b}_2, \ldots , \mathrm{b}_{1982} . We then compare b1982\mathrm{b}_{1982} and b1981\mathrm{b}_{1981} . If b1981>b1982\mathrm{b}_{1981} > \mathrm{b}_{1982} , we swap them. We then compare b1980\mathrm{b}_{1980} and (the new) b1981\mathrm{b}_{1981} . So we arrive finally at c1,c2,…,c1982\mathrm{c}_1, \mathrm{c}_2, \ldots , \mathrm{c}_{1982} . We find that a100=c100\mathrm{a}_{100} = \mathrm{c}_{100} . What value is a100\mathrm{a}_{100} ?

    Dataset text NuminaMath olympiads. Quoted with source.

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