blob: b083e31f838f34a785a9056aaf56f2e7eab7f0f1 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
|
# Uses python3
import sys
from collections import namedtuple
Segment = namedtuple('Segment', 'start end')
# def getSortedListOfSegs(segList):
# segList.sort()
# return segList
#
#
# def getOptimalPoints(segList):
# if len(segList) == 1:
# return [segList[0].start]
# if segList[0].end <= segList[1].start:
# result = [segList[0].end]
# if segList[1].start == segList[1].end:
# if len(segList) == 2:
# return result
# else:
# result.extend(getOptimalPoints(segList[2:]))
# return result
# else:
# if segList[0].end >= segList[1].end:
# result = [segList[1].end]
# del(segList[1])
# result.extend(getOptimalPoints(segList[1:]))
# return result
# else:
# result = [segList[0].end]
# result.extend(getOptimalPoints(segList[1:]))
# return result
#
#
# def getOptimalPoints1(segList):
# if len(segList) == 1:
# return [segList[0].start]
# if segList[0] == segList[1]:
# return getOptimalPoints1(segList[1:])
# if segList[0].start == segList[0].end:
# result = [segList[0].end]
# result.extend(getOptimalPoints1(segList[1:]))
# return result
# if segList[0].start == segList[1].start:
# result = [segList[0].end]
# result.extend(getOptimalPoints1(segList[1:]))
# return result
# if segList[0].end < segList[1].start:
# result = [segList[0].end]
# result.extend(getOptimalPoints1(segList[1:]))
# return result
# else:
# if segList[0].end == segList[1].start:
# result = [segList[0].end]
# result.extend(getOptimalPoints1(segList[1:]))
# return result
# else: # segList[0].end > segList[1].start
# if segList[0].end < segList[1].end:
# result = [segList[0].end]
# result.extend(getOptimalPoints1(segList[1:]))
# return result
# if segList[0].end == segList[1].end:
# result = [segList[1].end]
# result.extend(getOptimalPoints1(segList[1:]))
# return result
# else:
# result = [segList[1].end]
# del(segList[1])
# result.extend(getOptimalPoints1(segList))
# return result
def getOptimalPoints2(segList):
index = 0
points = []
while index < len(segList):
points.append(segList[index].end)
index = index + 1
while index < len(segList) and segList[index].start <= points[-1]:
if segList[index].end < points[-1]:
points[-1] = segList[index].end
index = index + 1
return points
if __name__ == '__main__':
input = sys.stdin.read()
n, *data = map(int, input.split())
segments = set(map(lambda x: Segment(x[0], x[1]), zip(data[::2], data[1::2])))
segments = list(segments)
segments.sort()
points = getOptimalPoints2(segments)
print(len(points))
for p in points:
print(p, end=' ')
|
