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#!/usr/bin/env python3
# Challenge 074
#
# TASK #1 > Majority Element
# Submitted by: Mohammad S Anwar
# You are given an array of integers of size $N.
#
# Write a script to find the majority element. If none found then print -1.
#
# Majority element in the list is the one that appears more than
# floor(size_of_list/2).
#
# Example 1
# Input: @A = (1, 2, 2, 3, 2, 4, 2)
# Output: 2, as 2 appears 4 times in the list which is more than floor(7/2).
#
# Example 2
# Input: @A = (1, 3, 1, 2, 4, 5)
# Output: -1 as none of the elements appears more than floor(6/2).
import sys
def majority_elem(a):
# count instances of each element, get max
count = {}
max_count = 0
max_elem = None
for x in a:
if x in count:
count[x] += 1
else:
count[x] = 1
if count[x] > max_count:
max_count, max_elem = count[x], x
# check if majority
if max_count > int(len(a)/2):
return max_elem
else:
return -1
a = [int(x) for x in sys.argv[1:]]
print(majority_elem(a))
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