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First solution in Uncategorized category for Count Inversions by Mahoter
def count_inversion(sequence):
"""
Count inversions in a sequence of numbers
"""
a = 0
for idx in range(len(sequence)-1):
for idx2 in range(idx, len(sequence)):
#print (sequence[idx], sequence[idx2])
if sequence[idx] > sequence[idx2]:
a += 1
return a
if __name__ == '__main__':
#These "asserts" using only for self-checking and not necessary for auto-testing
assert count_inversion((1, 2, 5, 3, 4, 7, 6)) == 3, "Example"
assert count_inversion((0, 1, 2, 3)) == 0, "Sorted"
assert count_inversion((99, -99)) == 1, "Two numbers"
assert count_inversion((5, 3, 2, 1, 0)) == 10, "Reversed"
Jan. 17, 2016
