although和but
时间: 2024-04-05 07:30:54 浏览: 282
"although" 和 "but" 是英语中的连词,它们都用于连接两个句子或短语。
"Although" 通常用于引出一个与前面说的内容相反的情况,例如:Although it was raining, we still went for a walk.(尽管下雨了,我们还是去散步了。)
"But" 则用于表达转折或相反的意思,例如:I want to go to the party, but I have to finish my homework first.(我想去参加派对,但我必须先完成我的家庭作业。)
相关问题
although和不听可以连用吗
“不听”这个词语在这里可能不太合适,因为它的意思是“不听从”或“不听取”,而不是表示与前面说的内容相反的情况。
如果你想用一个表示相反情况的词语来连接句子,可以使用 “although” 和 “but” 中的任意一个。例如:
- Although she studied hard, she still failed the exam.
- But she didn’t study at all, and she passed the exam anyway.
请注意,这两个词语在同一句话中使用可能会产生语法问题,因为它们表达的意思是不同的。
John wantsto have a journey around Ireland. He has many items that he likes to carry with him, but although he has three suitcases, unfortunately, he cannot accommodate all his itemsin the suitcases. Thus, he needs to decide which items to pick. He knows the size and worth of each item. Therefore, he likes to pick the items so that the total values of the selected items be maximum. There are several items that he cannot take part of them, like his violin. But some of them, he can take part of them like sugar. You need to write a program in Java to help John select his items and tell John that each item should be put in which suitcase. The input of the program is the number of suitcases that John has and also the capacity of each of them. In addition, the total number of the items, the size and worth of each, and whether John can take a part of the item.
好的,这是一个背包问题(Knapsack Problem),我们可以使用动态规划算法来解决。首先,我们需要定义以下几个变量:
- `n`:旅行者带的物品总数
- `m`:旅行者拥有的行李箱数量
- `w[i]`:第 `i` 个物品的体积
- `v[i]`:第 `i` 个物品的价值
- `t[i]`:第 `i` 个物品是否可以分开带(是则为 1,否则为 0)
- `c[j]`:第 `j` 个行李箱的容量
- `f[i][j][k]`:前 `i` 个物品,放置在前 `j` 个行李箱中,第 `k` 个行李箱还剩余的容量时的最大价值
那么,我们可以得到状态转移方程:
- 当第 `i` 个物品不能分开带时,有:
$$
f[i][j][k] = \max \{f[i-1][j][k], f[i-1][j-1][c[j]] + v[i]\}
$$
- 当第 `i` 个物品能分开带时,有:
$$
f[i][j][k] = \max \{f[i-1][j][k], f[i-1][j-1][c[j]] + v[i], f[i-1][j][k-w[i]] + v[i]\}
$$
最终,答案即为 $f[n][m][0]$。具体实现可以参考以下 Java 代码:
```java
public class Knapsack {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt(); // 物品总数
int m = scanner.nextInt(); // 行李箱数量
int[] w = new int[n+1]; // 物品体积
int[] v = new int[n+1]; // 物品价值
int[] t = new int[n+1]; // 物品是否可分开带
int[] c = new int[m+1]; // 行李箱容量
for (int i = 1; i <= n; i++) {
w[i] = scanner.nextInt();
v[i] = scanner.nextInt();
t[i] = scanner.nextInt();
}
for (int i = 1; i <= m; i++) {
c[i] = scanner.nextInt();
}
int[][][] f = new int[n+1][m+1][1001]; // 前 i 个物品,放置在前 j 个行李箱中,第 k 个行李箱还剩余的容量时的最大价值
for (int i = 1; i <= n; i++) {
for (int j = 1; j <= m; j++) {
for (int k = 0; k <= c[j]; k++) {
f[i][j][k] = f[i-1][j][k];
if (k >= w[i]) {
f[i][j][k] = Math.max(f[i][j][k], f[i-1][j][k-w[i]] + v[i]);
}
}
if (t[i] == 1) {
for (int k = 0; k <= c[j]; k++) {
if (k >= w[i]) {
f[i][j][k] = Math.max(f[i][j][k], f[i-1][j-1][c[j]] + v[i]);
}
}
}
}
}
System.out.println(f[n][m][0]);
scanner.close();
}
}
```
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