# Python | Count overlapping substring in a given string

Given a string and a sub-string, the task is to get the count of overlapping substring from the given string.

Note that in Python, the `count()` function returns the number of substrings in a given string, but it does not give correct results when two occurrences of the substring overlap. Consider this example –

 `string ``=` `"GeeksforGeeksforGeeksforGeeks"` ` `  `print``(string.count(``"GeeksforGeeks"``)) `

Output:

`2`

The output we got here is 2, but the expected output is 3 since we also wanted to count the occurrence of overlapped sub-string.

In order to solve this problem, we can use `find()` function in Python. It returns the start position of the first occurrence of substring in the given string, then we increment this position by 1 and continue the search from that position till the end of the string.

Below is the implementation –

 `def` `CountOccurrences(string, substring): ` `    ``# Initialize count and start to 0 ` `    ``count ``=` `0` `    ``start ``=` `0` ` `  `    ``# Search through the string till ` `    ``# we reach the end of it ` `    ``while` `start < ``len``(string): ` ` `  `        ``# Check if a substring is present from ` `        ``# 'start' position till the end ` `        ``flag ``=` `string.find(substring, start) ` ` `  `        ``if` `flag !``=` `-``1``: ` `            ``# If a substring is present, move 'start' to ` `            ``# the next position from start of the substring ` `            ``start ``=` `flag ``+` `1` ` `  `            ``# Increment the count ` `            ``count ``+``=` `1` `        ``else``: ` `            ``# If no further substring is present ` `            ``# return the value of count ` `            ``return` `count ` ` `  `# Driver Code ` `string ``=` `"GeeksforGeeksforGeeksforGeeks"` `print``(CountOccurrences(string, ``"GeeksforGeeks"``)) `

Output:

```3
```

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