第一题可以不用map，在原数组上直接改就行 public int timeRequiredToBuyCounpons(int[] coupons, int m) { // write code here ArrayDeque<Integer> queue = new ArrayDeque<>(); for (int i = 0; i < coupons.length; i++) { queue.add(i); } int ans = 0; while (coupons[m] != 0) { if (queue.isEmpty()) break; Integer peopleIndex = queue.poll(); int count = coupons[peopleIndex]; count -= 1; ans += 10; coupons[peopleIndex] = count; if (count == 0) continue; queue.add(peopleIndex); } return ans; }