Input: {"operations":["SummaryRanges","addNum","getIntervals","addNum","getIntervals","addNum","getIntervals","addNum","getIntervals","addNum","getIntervals"],"args":[[],[1],[],[3],[],[7],[],[2],[],[6],[]]}
Output: [null, null, [[1,1]], null, [[1,1],[3,3]], null, [[1,1],[3,3],[7,7]], null, [[1,3],[7,7]], null, [[1,3],[6,7]]]