Nested Dictionaries
Dictionaries within dictionaries
Interview Relevant: Complex data structures
Nested Dictionaries
Dictionaries containing other dictionaries.
Code Examples
Working with nested dictionaries.
python
1# Nested dictionary
2users = {
3 "alice": {"age": 25, "city": "NYC"},
4 "bob": {"age": 30, "city": "LA"}
5}
6
7# Access nested values
8users["alice"]["age"] # 25
9
10# Safe nested access
11users.get("charlie", {}).get("age", "Unknown")
12
13# Modify nested
14users["alice"]["age"] = 26
15
16# Add nested key
17users["alice"]["email"] = "alice@example.com"
18
19# Iterate nested
20for name, info in users.items():
21 print(f"{name}: {info['city']}")
22
23# Flatten nested dict
24flat = {f"{k1}_{k2}": v2
25 for k1, v1 in users.items()
26 for k2, v2 in v1.items()}