You are given n activities with their start and finish times. Select the maximum number of activities that can be performed by a single person, assuming that a person can only work on a single activity at a time. Example:
Example 1 : Consider the following 3 activities sorted by finish time. start[] = {10, 12, 20}; finish[] = {20, 25, 30}; A person can perform at most two activities. The maximum set of activities that can be executed is {0, 2} [ These are indexes in start[] and finish[] ] Example 2 : Consider the following 6 activities sorted by finish time. start[] = {1, 3, 0, 5, 8, 5}; finish[] = {2, 4, 6, 7, 9, 9}; A person can perform at most four activities. The maximum set of activities that can be executed is {0, 1, 3, 4} [ These are indexes in start[] and finish[] ]
Python
"""The following implementation assumes that the activities are already sorted according to their finish time""" """Prints a maximum set of activities that can be done by a single person, one at a time""" # n --> Total number of activities # s[]--> An array that contains start time of all activities # f[] --> An array that contains finish time of all activities def printMaxActivities(s, f ):
n = len (f)
print "The following activities are selected"
# The first activity is always selected
i = 0
print i,
# Consider rest of the activities
for j in xrange (n):
# If this activity has start time greater than
# or equal to the finish time of previously
# selected activity, then select it
if s[j] > = f[i]:
print j,
i = j
# Driver program to test above function s = [ 1 , 3 , 0 , 5 , 8 , 5 ]
f = [ 2 , 4 , 6 , 7 , 9 , 9 ]
printMaxActivities(s, f) # This code is contributed by Nikhil Kumar Singh |
Output:
The following activities are selected 0 1 3 4
Please refer complete article on Activity Selection Problem | Greedy Algo-1 for more details!
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