题目链接 问题分析 没有想到母函数的做法…… 其实直接看题思路挺简单的。发现如果每种花都有无限多的话,问题变得十分简单,答案就是\(s+n-1\choose n - 1\)。然后发现\(n\)只有\(20\),于是大力容斥一波就完事了。 参考代码 #include <cstdio>const long long Max_n = 30;const long long Mod = 10000000
题目 n n n种颜色,每种颜色有 a i a_i ai枝花,现挑出 m m m朵,使没有颜色完全相同的方案 分析 可以发现,这道题是求多重集的组合数,根据容斥原理也就是 C k + r − 1 k − 1 − ∑ i = 1 k C k + r − n i − 2 k − 1 + ∑ 1 ≤ i < j ≤ k C k + r − n i − n j − 3 k − 1 −
C. Watering Flowers time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output A flowerbed has many flowers and two fountains. You
[Usaco2007 Jan]Protecting the Flowers 护花 Description Farmer John went to cut some wood and left N (2 <= N <= 100,000) cows eating the grass, as usual. When he returned, he found to his horror that t
Problem You have a long flowerbed in which some of the plots are planted, and some are not. However, flowers cannot be planted in adjacent plots. Given an integer array flowerbed containing 0’s and
605. Can Place Flowers You have a long flowerbed in which some of the plots are planted, and some are not. However, flowers cannot be planted in adjacent plots. Given an integer array flowerbed cont
文章目录 1.导入包2.加载数据3.数据预处理4.数据增强5.预处理层的两种方法6.把与处理层用在数据集上7.训练模型8.自定义数据增强9.Using tf.image tf_flowers数据集 1.导入包 import matplotlib.pyplot as pltimport numpy as npimport tensorflow as tfimp
Description Farmer John went to cut some wood and left N (2 ≤ N ≤ 100,000) cows eating the grass, as usual. When he returned, he found to his horror that the cluster of cows was in his garden eating