defaultDict.py.0

#!/bin/env python3
"""

defaultdict tool is a containter in the collections class of Python.
It is similar to the usual dictionary (dict) container, but it has one
difference: The value fields' data type is specified upon initialization.

INPUT: 1 + n + m lines
 int n and m
 next n lines:
   words belonging to group A
 next m lines:
   words belonging to group B

For each group B word,
 find position in the group A list
 pos1 pos2 pos3


OUTPUT: m lines
 ea. line should contain the positions of the occurences of
 group B word in the group A list separated by spaces.
 Print the indices of ea. occurrence of m in group A.
 If it does not appear, print -1.

"""


import collections


def get_positions(a, w):
    """
    INPUT:
    a = list of words
    i = word to look for
    OUTPUT:
    list of positions of w in a  or -1,
        where position = zero-index + 1
    """
    f = a.count(w)
    position_list = []

    if f == 0:
        return [-1]

    pos = 0
    for i in range(f):
        try:
            idx = a.index(w, pos)
            pos = idx + 1
        except ValueError:
            pos = -1
        position_list.append(pos)

    assert len(position_list) == f

    return position_list


if __name__ == '__main__':
    n, m = map(int, input().split())
    group_A = list()
    group_B = list()
    positions = collections.defaultdict(list)
    for _ in range(n):
        group_A.append(input())
    for _ in range(m):
        group_B.append(input())
    for word in group_B:
        positions[word] = get_positions(group_A, word)
        print(*positions[word])