Python: Grouping a sequence of key-value pairs into a dictionary of lists
Python dictionary: Exercise-46 with Solution
Write a Python program to create a dictionary grouping a sequence of key-value pairs into a dictionary of lists.
Sample Solution:
Python Code:
def grouping_dictionary(l):
result = {}
for k, v in l:
result.setdefault(k, []).append(v)
return result
colors = [('yellow', 1), ('blue', 2), ('yellow', 3), ('blue', 4), ('red', 1)]
print("Original list:")
print(colors)
print("\nGrouping a sequence of key-value pairs into a dictionary of lists:")
print(grouping_dictionary(colors))
Sample Output:
Original list: [('yellow', 1), ('blue', 2), ('yellow', 3), ('blue', 4), ('red', 1)] Grouping a sequence of key-value pairs into a dictionary of lists: {'yellow': [1, 3], 'blue': [2, 4], 'red': [1]}
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Previous: Write a Python program to check all values are same in a dictionary.
Next: Write a Python program to split a given dictionary of lists into list of dictionaries.
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