Python program to find Maximum value from dictionary whose key is present in the list

Last Updated : 01 Oct, 2020

Given a list with dictionary keys and a dictionary, extract maximum from dictionary values, whose key is present in list.

Examples:

Input : test_dict = {“Gfg”: 4, “is” : 5, “best” : 10, “for” : 11, “geeks” : 3}, test_list = [“Gfg”, “best”, “geeks”]
Output : 10
Explanation : Max value is 11, but not present in list, 10 is of key best, which is also in list.

Input : test_dict = {“Gfg”: 4, “is” : 5, “best” : 10, “for” : 11, “geeks” : 3}, test_list = [“Gfg”, “best”, “geeks”, “for”]
Output : 11
Explanation : Max. value, 11, present in list as well.

Method #1: Using loop

This is one of the ways in which this task can be performed. In this, we check for all the keys present in list and also maximum, then return the maximum available.

Python3

# Python3 code to demonstrate working of  
# Maximum value from List keys 
# Using loop  
  
# initializing dictionary 
test_dict = {"Gfg": 4, "is" : 5, "best" : 9, 
             "for" : 11, "geeks" : 3} 
  
# printing original dictionary 
print("The original dictionary is : " + str(test_dict)) 
  
# initializing list  
test_list = ["Gfg", "best", "geeks"] 
  
res = 0
for ele in test_list: 
      
    # checking for key in dictionary 
    if ele in test_dict: 
        res = max(res, test_dict[ele]) 
      
# printing result  
print("The required maximum : " + str(res))  

Output:

The original dictionary is : {‘Gfg’: 4, ‘is’: 5, ‘best’: 9, ‘for’: 11, ‘geeks’: 3}
The required maximum : 9

Method #2 : Using max() + list comprehension

This is yet another way in which this task can be performed. In this, we extract maximum using max() and shorthand list comprehension is used to iterate through values.

Python3

# Python3 code to demonstrate working of  
# Maximum value from List keys 
# Using max() + list comprehension 
  
# initializing dictionary 
test_dict = {"Gfg": 4, "is" : 5, "best" : 9,  
             "for" : 11, "geeks" : 3} 
  
# printing original dictionary 
print("The original dictionary is : " + str(test_dict)) 
  
# initializing list  
test_list = ["Gfg", "best", "geeks"] 
  
# maximum is 11, but not present in list,  
# hence 9 is output. 
res = max([test_dict[ele] for ele in test_list 
           if ele in test_dict]) 
  
# printing result  
print("The required maximum : " + str(res))  