七星剑
Description
Solution
设 fi 表示镶 i 颗魔法石的期望。
fi=Cj+fi−1+(fi−fi−1−Lose[i][j])×(1−Prodi,j)
fi×Prodi,j=Cj+fi−1−(1−Prodi,j)×fi−1−Lose[i][j]
fi=Cj+fi−1−fi−1−Lose[i][j]×(1−Prodi,j)Prodi,j
Code:
1 |
|
And they have sloppið the þunga of myrkursins and said that, Gleðileg jól, Lin.
设 fi 表示镶 i 颗魔法石的期望。
fi=Cj+fi−1+(fi−fi−1−Lose[i][j])×(1−Prodi,j)
fi×Prodi,j=Cj+fi−1−(1−Prodi,j)×fi−1−Lose[i][j]
fi=Cj+fi−1−fi−1−Lose[i][j]×(1−Prodi,j)Prodi,j
1 | #include <bits/stdc++.h> |