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Edit Distance

Problem Statement

Given strings s1 and s2, we need to transform s1 into s2 by deleting, inserting, or replacing characters. Write a function to calculate the count of the minimum number of edit operations.

Example 1:

Input: s1 = "bat"
       s2 = "but"
Output: 1
Explanation: We just need to replace 'a' with 'u' to transform s1 to s2.

Example 2:

Input: s1 = "abdca"
       s2 = "cbda"
Output: 2
Explanation: We can replace first 'a' with 'c' and delete second 'c'.

Example 3:

Input: s1 = "passpot"
       s2 = "ppsspqrt"
Output: 3 
Explanation: Replace 'a' with 'p', 'o' with 'q', and insert 'r'.

Constraints:

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