# DefaultDict Tutorial in Python HackerRank Solution

Hello coders, In this post, you will learn how to solve DefaultDict Tutorial in Python HackerRank Solution. This problem is a part of the Python Hacker Rank series.

## DefaultDict Tutorial in Python HackerRank Solution

### problem

The defaultdict tool is a container in the collections class of Python. It’s similar to the usual dictionary (dict) container, but the only difference is that a defaultdict will have a default value if that key has not been set yet. If you didn’t use a defaultdict you’d have to check to see if that key exists, and if it doesn’t, set it to what you want.

For Example :

```from collections import defaultdict
d = defaultdict(list)
d['python'].append("awesome")
d['something-else'].append("not relevant")
d['python'].append("language")
for i in d.items():
print i
```

This prints :

```('python', ['awesome', 'language'])
('something-else', ['not relevant'])
```

In this challenge, you will be given 2 integers, n and m. There are n words, which might repeat, in word group A. There are m words belonging to word group B. For each m words, check whether the word has appeared in group A or not. Print the indices of each occurrence of m in group A. If it does not appear, print -1.

#### Constraints :

• 1 <= n <= 10000
• 1 <= m <= 100
• 1 <= length of each word in the input <= 100

#### Input Format :

The first line contains integers, n and m separated by a space.
The next n lines contains the words belonging to group A.
The next m lines contains the words belonging to group B.

#### Output Format :

Output m lines.
The ith line should contain the 1-indexed positions of the occurrences of the ith word separated by spaces.

```5 2
a
a
b
a
b
a
b
```

```1 2 4
3 5
```

#### Explanation :

‘a’ appeared 3 times in positions 1, 2 and 4.
‘b’ appeared 2 times in positions 3 and 5.
In the sample problem, if ‘c’ also appeared in word group B, you would print -1.

### DefaultDict Tutorial in Python HackerRank Solution

```# DefaultDict Tutorial in Python - Hacker Rank Solution
# Python 3
# Enter your code here. Read input from STDIN. Print output to STDOUT
# DefaultDict Tutorial in Python - Hacker Rank Solution START
from collections import defaultdict
n, m = map(int,input().split())
a = defaultdict(list)
for i in range(1, n + 1):
a[input()].append(i)
for i in range(1, m + 1):
key = input()
if len(a[key]) > 0:
print(" ".join(str(c) for c in a[key]))
else:
print(-1)```

Disclaimer: The above Problem (DefaultDict Tutorial in Python ) is generated by Hackerrank but the Solution is Provided by Chase2Learn. This tutorial is only for Educational and Learning purposes. Authority if any of the queries regarding this post or website fill the following contact form thank you.

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