715. Range Module

715. Range Module

• 题目描述：A Range Module is a module that tracks ranges of numbers. Your task is to design and implement the following interfaces in an efficient manner.

  addRange(int left, int right) Adds the half-open interval [left, right), tracking every real number in that interval. Adding an interval that partially overlaps with currently tracked numbers should add any numbers in the interval [left, right) that are not already tracked.

  queryRange(int left, int right) Returns true if and only if every real number in the interval [left, right) is currently being tracked.

  removeRange(int left, int right) Stops tracking every real number currently being tracked in the interval [left, right).

• 题目大意：实现一个区间模型，可以实现插入，查询，删除区间的功能。

• 思路：使用treemap会对键值对升序排序的特征完成功能。

• 代码:

  class RangeModule {      TreeMap<Integer, Integer> map;      public RangeModule() {          map = new TreeMap<>();      }      public void addRange(int left, int right) {          if (right <= left) {              return;          }          Integer start = map.floorKey(left);          Integer end = map.floorKey(right);//            如果当前的区间不存在重合的部分          if (start == null && end == null) {              map.put(left, right);          } else if (start != null && map.get(start) >= left) {              map.put(start, Math.max(map.get(end), Math.max(map.get(start), right)));          } else {              map.put(left, Math.max(map.get(end), right));          }          Map<Integer, Integer> subMap = map.subMap(left, false, right, true);          Set<Integer> set = new HashSet<>(subMap.keySet());          map.keySet().removeAll(set);      }      public boolean queryRange(int left, int right) {          Integer start = map.floorKey(left);          if (start == null) return false;          return map.get(start) >= right;      }      public void removeRange(int left, int right) {          if (right <= left) {              return;          }          Integer start = map.floorKey(left);          Integer end = map.floorKey(right);          if (end != null && map.get(end) > right) {              map.put(right, map.get(end));          }          if (start != null && map.get(start) > left) {              map.put(start, left);          }          // clean up intermediate intervals          Map<Integer, Integer> subMap = map.subMap(left, true, right, false);          Set<Integer> set = new HashSet(subMap.keySet());          map.keySet().removeAll(set);      }  }/*** Your RangeModule object will be instantiated and called as such:* RangeModule obj = new RangeModule();* obj.addRange(left,right);* boolean param_2 = obj.queryRange(left,right);* obj.removeRange(left,right);*/