Create points_and_segments.py

Course 1 - Algorithmic Toolbox/week4_divide_and_conquer/5_organizing_a_lottery/points_and_segments.py

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+import sys
+from collections import defaultdict
+
+
+def fast_count_segments(zippedList,points):
+    elements = []
+    d = defaultdict(list)
+
+    for i in zippedList:
+        elements.append([i[0],'l'])
+    for x in range(len(points)):
+        elements.append([points[x],'p'])
+    for j in zippedList:
+        elements.append([j[1],'r'])
+
+    elements.sort(key=lambda x: x[1])
+    elements.sort(key=lambda x: x[0])
+    print(elements)
+    count = 0
+
+    for x in elements:
+        if x[1] == 'l':
+            count += 1
+        if x[1] == 'r':
+            count -= 1
+        if x[1] == 'p':
+            d[x[0]] = max(count,0)
+    return d
+
+
+def naive_count_segments(starts, ends, points):
+    cnt = [0] * len(points)
+    for i in range(len(points)):
+        for j in range(len(starts)):
+            if starts[j] <= points[i] <= ends[j]:
+                cnt[i] += 1
+    return cnt
+
+if __name__ == '__main__':
+    data = list(map(int, sys.stdin.read().split()))
+    n = data[0]
+    m = data[1]
+    starts = data[2:2 * n + 2:2]
+    ends   = data[3:2 * n + 2:2]
+    points = data[2 * n + 2:]
+    zippedList = list(zip(starts,ends))
+    cnt = fast_count_segments(zippedList, points)
+    for x in points:
+        print(cnt[x], end=' ')