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# Python – Keys Values equal frequency

• Last Updated : 25 Nov, 2020

Given a dictionary, count instances where keys are equal to values.

Input : test_dict = {5:5, 8:9, 7:8, 1:2, 10:10, 4:8}
Output : 2
Explanation : At 2 instances, keys are equal to values.

Input : test_dict = {5:4, 8:9, 7:8, 1:2, 10:10, 4:8}
Output : 1
Explanation : At 1 instance, key is equal to value.

Method #1 : Using loop

In this, we count instances where keys are equal to values and increment the counter accordingly.

## Python3

 `# Python3 code to demonstrate working of``# Keys Values equal frequency``# Using loop`` ` `# initializing dictionary``test_dict ``=` `{``5``: ``5``, ``8``: ``9``, ``7``: ``7``, ``1``: ``2``, ``10``: ``10``, ``4``: ``8``}`` ` `# printing original dictionary``print``(``"The original dictionary is : "` `+` `str``(test_dict))`` ` `res ``=` `0``for` `key ``in` `test_dict:`` ` `    ``# checking for equality and incrementing counter``    ``if` `key ``=``=` `test_dict[key]:``        ``res ``+``=` `1`` ` `# printing result``print``(``"The required frequency : "` `+` `str``(res))`
Output
```The original dictionary is : {5: 5, 8: 9, 7: 7, 1: 2, 10: 10, 4: 8}
The required frequency : 3
```

Method #2 : Using sum() + list comprehension

In this, task of counting is performed using sum(), when equal key-values are found, 1 is appending to list, and then at end, each value is summed.

## Python3

 `# Python3 code to demonstrate working of``# Keys Values equal frequency``# Using sum() + list comprehension`` ` `# initializing dictionary``test_dict ``=` `{``5``: ``5``, ``8``: ``9``, ``7``: ``7``, ``1``: ``2``, ``10``: ``10``, ``4``: ``8``}`` ` `# printing original dictionary``print``(``"The original dictionary is : "` `+` `str``(test_dict))`` ` `# computing summation to get frequency``res ``=` `sum``([``1` `for` `key ``in` `test_dict ``if` `key ``=``=` `test_dict[key]])`` ` `# printing result``print``(``"The required frequency : "` `+` `str``(res))`
Output
```The original dictionary is : {5: 5, 8: 9, 7: 7, 1: 2, 10: 10, 4: 8}
The required frequency : 3
```

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