Alice and Bob made a list of topics and both of them voted if they like or dislike the topic. They wrote 0 to denote dislike and 1 to denote like. The task is to count the number of topics that both of them like or dislike.

**Examples:**

Input:alice = “010101” bob = “101101”Output:3

alice and bob both like 4th and 6th topics and dislike the 5th topic. Hence, the output is 3.

Input:alice = “111111” bob = “000000”Output:0

There are no common likes or dislikes between alice and bob. Hence, the output is 0.

Input:alice = “110000” bob = “110011”Output:4

alice and bob both like 1st and 2nd topics and dislike 3rd and 4th topics. Hence, the result is 4.

**Approach:**

- First, we have to iterate through each character of the string consisting of the likes and dislikes of alice.
- Then, we have to compare it with the corresponding entry of the string consisting of the likes and dislikes of bob.
- Finally, we will count the number of similar entries and print.

Below is the implementation.

`# function to obtain no ` `# of topics both alice and ` `# bob like ` `def` `commontopics(alice, bob):` ` ` ` ` `# initiate count with 0` ` ` `count ` `=` `0` ` ` ` ` `# iterating through alice` ` ` `for` `i ` `in` `range` `(` `0` `,` `len` `(alice)):` ` ` ` ` `# comparing with corresponding` ` ` `# bob entry` ` ` `if` `alice[i] ` `=` `=` `bob[i]:` ` ` ` ` `# counting similar entries` ` ` `count ` `+` `=` `1` ` ` ` ` `# printing the count ` ` ` `print` `(count) ` ` ` `#main function ` `def` `main():` ` ` ` ` `commontopics(` `"010101"` `, ` `"101101"` `)` ` ` `commontopics(` `"111111"` `, ` `"000000"` `)` ` ` `commontopics(` `"110000"` `, ` `"110011"` `)` ` ` ` ` `# driver code` `if` `__name__ ` `=` `=` `"__main__"` `:` ` ` `main()` ` ` `# This code is contributed by SrujayReddy` |

**Output:**

3 0 4

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