做完没时间编译，大家看看这个代码能对百分之多少？ import java.util.Scanner; publicclass Main { staticclass Item { int type = 0; boolean isUse = false; public Item(int t, boolean b) { type = t; isUse= b; } } public static void main(String[] args) { Scanner s = new Scanner(System.in); while (s.hasNext()) { int times = s.nextInt(); int size  = s.nextInt(); int count = 1; Item data[] = new Item[size]; for (int i = 0; i < size; i++) { data[i] = new Item(0, false); } int now = 0; while (now < times) { now++; String com = s.next(); if (com.equals("new")) { int d = s.nextInt(); int i = 0; for (i = size - 1; i >= 0; i--) { if (data[i].isUse == true)  break; } if (i + 1 <= size - 1) { if (size - (i + 1) >= d) { for (int j = 0; j < d; j++) { data[j + i +1] = new Item(count, true); } System.out.println(count++); } else { System.out.println("NULL"); } } } else if (com.equals("del")){ int tt = s.nextInt(); boolean isT = false; for (int i = 0; i < size; i++) { if (data[i].type == tt) { data[i].isUse = false; isT = true; } } if (isT == false) { System.out.println("ILLEGAL_OPERATION"); }  } else if (com.equals("def")) { Item two[] = new Item[size]; for (int i = 0; i < size; i++) { two[i] = new Item(0, false); } int tii = 0; for (int i = 0; i < size; i++) { if (data[i].isUse == true) { two[tii].isUse = true; two[tii].type = data[i].type; tii++; } } data = two; } } } } }