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两侧同时换到之前的修订记录 前一修订版 后一修订版 | 前一修订版 | ||
2020-2021:teams:legal_string:组队训练比赛记录:contest17 [2021/09/01 09:20] lgwza [题解] |
2020-2021:teams:legal_string:组队训练比赛记录:contest17 [2021/09/05 10:20] (当前版本) jxm2001 [题意] |
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行 6: | 行 6: | ||
| C | 0 | 0 | 0 | | | C | 0 | 0 | 0 | | ||
| D | 0 | 0 | 0 | | | D | 0 | 0 | 0 | | ||
- | | E | 2 | 0 | 0 | | + | | E | 2 | 2 | 0 | |
| H | 2 | 0 | 0 | | | H | 2 | 0 | 0 | | ||
| J | 2 | 0 | 0 | | | J | 2 | 0 | 0 | | ||
行 18: | 行 18: | ||
$$ | $$ | ||
- | \sum_{i=1}^n\sum_{j=1}^n {i+j\choose j}f(i,j)\\ | + | \sum_{i=1}^n\sum_{j=1}^n {i+j\choose j}f(i+j,i)\\ |
f(i,j)= | f(i,j)= | ||
\begin{cases} | \begin{cases} |