# 1.8 字典的运算¶

## 解决方案¶

```prices = {
'ACME': 45.23,
'AAPL': 612.78,
'IBM': 205.55,
'HPQ': 37.20,
'FB': 10.75
}
```

```min_price = min(zip(prices.values(), prices.keys()))
# min_price is (10.75, 'FB')
max_price = max(zip(prices.values(), prices.keys()))
# max_price is (612.78, 'AAPL')
```

```prices_sorted = sorted(zip(prices.values(), prices.keys()))
# prices_sorted is [(10.75, 'FB'), (37.2, 'HPQ'),
#                   (45.23, 'ACME'), (205.55, 'IBM'),
#                   (612.78, 'AAPL')]
```

```prices_and_names = zip(prices.values(), prices.keys())
print(min(prices_and_names)) # OK
print(max(prices_and_names)) # ValueError: max() arg is an empty sequence
```

## 讨论¶

```min(prices) # Returns 'AAPL'
max(prices) # Returns 'IBM'
```

```min(prices.values()) # Returns 10.75
max(prices.values()) # Returns 612.78
```

```min(prices, key=lambda k: prices[k]) # Returns 'FB'
max(prices, key=lambda k: prices[k]) # Returns 'AAPL'
```

```min_value = prices[min(prices, key=lambda k: prices[k])]
```

```>>> prices = { 'AAA' : 45.23, 'ZZZ': 45.23 }
>>> min(zip(prices.values(), prices.keys()))
(45.23, 'AAA')
>>> max(zip(prices.values(), prices.keys()))
(45.23, 'ZZZ')
>>>
```