邮局选址问题分治法Java代码实现
时间: 2024-02-23 07:25:11 浏览: 203
以下是一个简单的分治法邮局选址问题的Java代码实现:
```java
import java.util.Arrays;
public class PostalOffice {
public static void main(String[] args) {
int[] houses = {2, 4, 6, 8, 10};
int numOffices = 3;
int minDist = getMinDistance(houses, numOffices);
System.out.println("Minimum distance: " + minDist);
}
public static int getMinDistance(int[] houses, int numOffices) {
int n = houses.length;
int[][] dp = new int[numOffices + 1][n];
for (int i = 0; i <= numOffices; i++) {
Arrays.fill(dp[i], -1);
}
return minDistance(houses, numOffices, 0, dp);
}
public static int minDistance(int[] houses, int numOffices, int start, int[][] dp) {
int n = houses.length;
if (numOffices == 0) {
return 0;
}
if (dp[numOffices][start] != -1) {
return dp[numOffices][start];
}
int minDist = Integer.MAX_VALUE;
for (int i = start; i <= n - numOffices; i++) {
int dist = getDistance(houses, start, i) + minDistance(houses, numOffices - 1, i + 1, dp);
minDist = Math.min(minDist, dist);
}
dp[numOffices][start] = minDist;
return minDist;
}
public static int getDistance(int[] houses, int start, int end) {
int mid = (start + end) / 2;
int dist = 0;
for (int i = start; i <= end; i++) {
dist += Math.abs(houses[i] - houses[mid]);
}
return dist;
}
}
```
这个实现使用了一个二维数组来存储子问题的解,以避免重复计算。函数`minDistance`采用递归的方式计算最小距离,并返回结果。`getDistance`函数计算了一组房子中心的距离。最后,`getMinDistance`函数初始化了二维数组,并调用`minDistance`函数来计算最小距离。
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