{"trustable":false,"sections":[{"title":"","value":{"format":"MD","content":"\n\n给出N个区间,将其不重叠地放在数轴上,至少需要几个数轴?\n注意: [1, 2],[2, 3]算作重叠。\n\n请输出数轴数量,并按顺序输出每一个区间的安排(数轴编号1,2,3。。。)"}},{"title":"Input","value":{"format":"MD","content":"\n 第一行输入一个数N( N不超过50000)\n接下来把每个区间左右端点输入。"}},{"title":"Output","value":{"format":"MD","content":"输出第一行为数轴数量\n接下来每一行输出每个区间的安排"}},{"title":"Sample Input","value":{"format":"MD","content":"\u003cpre class\u003d\"sio\"\u003e5\n1 10\n2 4\n3 6\n5 8\n4 7\u003c/pre\u003e"}},{"title":"Sample Output","value":{"format":"MD","content":"\u003cpre class\u003d\"sio\"\u003e4\n1\n2\n3\n2\n4\u003c/pre\u003e"}}]}