java 最低列车平台调度

Posted 2021-05-08

import java.util.*;
public class MinTrainPlatforms {
    public static void main(String args[]) {
        MinTrainPlatforms minTrainPlatforms = new MinTrainPlatforms();
        int[][] arrival = {
          null,
          {},
          {1},
          {2,3,5,7,9},
          {2,3,4,5},
          {200,210,300,320,350,500}
        };
        
        int[][] departure = {
            null,
            {},
            {3},
            {9,4,6,8,10},
            {9,7,5,11},
            {230,320,340,400,430,520}
        };
        
        for(int i=0; i< arrival.length; i++) {
            System.out.println("Input: " + Arrays.toString(arrival[i]) + " " + Arrays.toString(departure[i]) + 
                               " Result: " + minTrainPlatforms.find(arrival[i], departure[i]));
        }
    }
    
    private int find(int[] arrival, int[] departure) {
        if(arrival == null || departure == null || 
          arrival.length != departure.length || arrival.length < 1) {
              return 0;
        }
        Arrays.sort(arrival);
        Arrays.sort(departure);
        int platforms = 0;
        int depatureIndex = 0;
        int maxPlatforms = 0;
        for(int i=0; i< arrival.length;i++) {
            if(arrival[i] < departure[depatureIndex]) {
                platforms++;
            } else {
                platforms--;
                depatureIndex++; 
            }
            maxPlatforms = Math.max(platforms, maxPlatforms);
        }
        return maxPlatforms;
    }
    
}