问对循环中的项目进行编号

EN

river_and_countries = { 
    'Nile' : 'egypt',
    'Amazon' : 'Brazil', 
    'yangtze' : 'china', 
    'mississippi' : 'united states of america', 
    'yenisei' : 'russia', 
    'ob' : 'russia', 
    'huang' : 'china', 
} 
num = len(river_and_countries) + 1
n = [value for value in range(1, num)] 

print(f"Following are the longest rivers in the world and their countries (by order):\n")
for x in n:
    for river, country in river_and_countries.items():
        if country == 'united states of america': 
            print(f"{x}. River {river.title()} is in the {country.title()}.") 
        else: 
            print(f"{x}. River {river.title()} in {country.title()}.") 

Following are the longest rivers in the world and their countries (by order):
    1. River Nile in Egypt.
    1. River Amazon in Brazil.
    1. River Yangtze in China.
    1. River Mississippi is in the United States Of America.
    1. River Yenisei in Russia.
    1. River Ob in Russia.
    1. River Huang in China.
    2. River Nile in Egypt.
    2. River Amazon in Brazil.
    2. River Yangtze in China.
    2. River Mississippi is in the United States Of America.
    2. River Yenisei in Russia.
    2. River Ob in Russia.
    2. River Huang in China.
    3. River Nile in Egypt.
    3. River Amazon in Brazil.
    3. River Yangtze in China.
    3. River Mississippi is in the United States Of America.
    3. River Yenisei in Russia.
    3. River Ob in Russia.
    3. River Huang in China.
    4. River Nile in Egypt.
    4. River Amazon in Brazil.
    4. River Yangtze in China.
    4. River Mississippi is in the United States Of America.
    4. River Yenisei in Russia.
    4. River Ob in Russia.
    4. River Huang in China.
    5. River Nile in Egypt.
    5. River Amazon in Brazil.
    5. River Yangtze in China.
    5. River Mississippi is in the United States Of America.
    5. River Yenisei in Russia.
    5. River Ob in Russia.
    5. River Huang in China.
    6. River Nile in Egypt.
    6. River Amazon in Brazil.
    6. River Yangtze in China.
    6. River Mississippi is in the United States Of America.
    6. River Yenisei in Russia.
    6. River Ob in Russia.
    6. River Huang in China.
    7. River Nile in Egypt.
    7. River Amazon in Brazil.
    7. River Yangtze in China.
    7. River Mississippi is in the United States Of America.
    7. River Yenisei in Russia.
    7. River Ob in Russia.
    7. River Huang in China.
    [Finished in 0.2s]