最多可达成的换楼请求数目

// Problem Statement: We need to find the maximum number of requests that can be satisfied under the condition that the net change in the number of employees in each building is zero.
// Solution Approach: Using Java Streams, we can recursively generate all possible subsets of the requests array and calculate the maximum valid subset by ensuring the net change condition is met.

import java.util.stream.IntStream;

public class SolutionStream {
    public int maximumRequests(int n, int[][] requests) {
        int[] count = new int[n];
        return maxRequests(n, requests, count, 0, 0);
    }

    private int maxRequests(int n, int[][] requests, int[] count, int index, int satisfied) {
        if (index == requests.length) {
            return IntStream.of(count).allMatch(c -> c == 0) ? satisfied : 0;
        }
        int from = requests[index][0];
        int to = requests[index][1];

        // Option 1: Do not satisfy this request
        int maxSatisfied = maxRequests(n, requests, count, index + 1, satisfied);

        // Option 2: Satisfy this request
        count[from]--;
        count[to]++;
        maxSatisfied = Math.max(maxSatisfied, maxRequests(n, requests, count, index + 1, satisfied + 1));
        count[from]++;
        count[to]--;

        return maxSatisfied;
    }
}