PAT甲级【1014 Waiting in Line】

1. 考察双向链表

2. import java.io.IOException;
   import java.io.InputStreamReader;
   import java.io.StreamTokenizer;
   import java.util.LinkedList;
   
   public class Main {
       @SuppressWarnings("uncheck")
       public static void main(String[] args) throws IOException {
           StreamTokenizer st = new StreamTokenizer(new InputStreamReader(System.in));
           int n, m, k, q;
           st.nextToken();
           n = (int) st.nval;
           st.nextToken();
           m = (int) st.nval;
           st.nextToken();
           k = (int) st.nval;
           st.nextToken();
           q = (int) st.nval;
   
           LinkedList<int[]>[] queue = new LinkedList[n];
           for (int i = 0; i < n; i++) {
               queue[i] = new LinkedList<>();
           }
           int[][] time = new int[k + 1][2];
           int[] cost = new int[k];
           for (int i = 0; i < k; i++) {
               st.nextToken();
               int v = (int) st.nval;
               cost[i] = v;
               if (i < m * n) {
                   if (queue[i % n].isEmpty()) {
                       queue[i % n].add(new int[]{i, 0, v});
                       time[i + 1] = new int[]{0, v};
                       continue;
                   }
                   int[] last = queue[i % n].getLast();
                   int finishedtime = last[2];
                   queue[i % n].add(new int[]{i, finishedtime, finishedtime + v});
                   time[i + 1] = new int[]{finishedtime, finishedtime + v};
               } else {
                   int min = 1000_000_00;
                   int minindex = -1;
                   for (int j = 0; j < n; j++) {
                       int[] first = queue[j].peekFirst();
                       if (min > first[2]) {
                           min = first[2];
                           minindex = j;
                       }
                   }
                   int[] last = queue[minindex].getLast();
                   int finishedtime = last[2];
   
                   queue[minindex].pollFirst();
                   queue[minindex].add(new int[]{i, finishedtime, finishedtime + v});
   
                   time[i + 1] = new int[]{finishedtime, finishedtime + v};
               }
           }
   
           int max = 540;
           for (int i = 1; i <= q; i++) {
               st.nextToken();
               int index = (int) st.nval;
               if (time[index][0] < max) {
                   System.out.println(format(time[index][1]));
               } else {
                   System.out.println("Sorry");
               }
           }
       }
   
       public static String format(int time) {
           int x = time / 60 + 8;
           int y = time % 60;
   
           StringBuilder sb = new StringBuilder();
           if (x < 10) {
               sb.append("0").append(x);
           } else {
               sb.append(x);
           }
           sb.append(":");
           if (y < 10) {
               sb.append("0").append(y);
           } else {
               sb.append(y);
           }
           return sb.toString();
       }
   }