Python – Combine two dictionaries having key of the first dictionary and value of the second dictionary

Given two dictionaries. The task is to merge them in such a way that the resulting dictionary contains the key from the first dictionary and value from the second dictionary.

Examples:

Input : test_dict1 = {“Gfg” : 20, “is” : 36, “best” : 100}, test_dict2 = {“Gfg2” : 26, “is2” : 20, “best2” : 70} 
Output : {‘Gfg’: 26, ‘is’: 20, ‘best’: 70} 
Explanation : Similar index keys’ values assigned to dictionary 1.

Input : test_dict1 = {“Gfg” : 20, “best” : 100}, test_dict2 = {“Gfg2” : 26, “best2” : 70} 
Output : {‘Gfg’: 26, ‘best’: 70} 
Explanation : Similar index keys’ values assigned to dictionary 1. 

Method #1 : Using loop + keys()

This is one way in which this task can be performed. In this, we extract all the keys using keys() and then assign required values inside loop.

Python3

# Python3 code to demonstrate working of
# Assign similar index values in Dictionary
# Using loop + keys()

# initializing dictionaries
test_dict1 = {"Gfg" : 20, "is" : 36, "best" : 100}
test_dict2 = {"Gfg2" : 26, "is2" : 19, "best2" : 70}

# printing original dictionaries
print("The original dictionary 1 is : " + str(test_dict1))
print("The original dictionary 2 is : " + str(test_dict2))

# extracting keys and values
keys1 = list(test_dict1.keys())
vals2 = list(test_dict2.values())

# assigning new values
res = dict()
for idx in range(len(keys1)):
    res[keys1[idx]] = vals2[idx]

# printing result
print("Mapped dictionary : " + str(res))

Output

The original dictionary 1 is : {‘Gfg’: 20, ‘is’: 36, ‘best’: 100}
The original dictionary 2 is : {‘Gfg2’: 26, ‘is2’: 19, ‘best2’: 70}
Mapped dictionary : {‘Gfg’: 26, ‘is’: 19, ‘best’: 70}

Method #2 : Using zip() + values()

This is yet another way in which this task can be performed. In this, we perform the task of mapping using zip(), extracting values using values().

Python3

# Python3 code to demonstrate working of
# Assign similar index values in Dictionary
# Using zip() + values()

# initializing dictionaries
test_dict1 = {"Gfg" : 20, "is" : 36, "best" : 100}
test_dict2 = {"Gfg2" : 26, "is2" : 19, "best2" : 70}

# printing original dictionaries
print("The original dictionary 1 is : " + str(test_dict1))
print("The original dictionary 2 is : " + str(test_dict2))

# using zip() to perform required dict. mapping
res = dict(zip(test_dict1, test_dict2.values()))

# printing result
print("Mapped dictionary : " + str(res))

Output

The original dictionary 1 is : {‘Gfg’: 20, ‘is’: 36, ‘best’: 100}
The original dictionary 2 is : {‘Gfg2’: 26, ‘is2’: 19, ‘best2’: 70}
Mapped dictionary : {‘Gfg’: 26, ‘is’: 19, ‘best’: 70}