## DEV Community

Abhishek Chaudhary

Posted on

# Remove All Occurrences of a Substring

Given two strings `s` and `part`, perform the following operation on `s` until all occurrences of the substring `part` are removed:

• Find the leftmost occurrence of the substring `part` and remove it from `s`.

Return `s` after removing all occurrences of `part`.

A substring is a contiguous sequence of characters in a string.

Example 1:

Input: s = "daabcbaabcbc", part = "abc"
Output: "dab"
Explanation: The following operations are done:

• s = "da*abc*baabcbc", remove "abc" starting at index 2, so s = "dabaabcbc".
• s = "daba*abc*bc", remove "abc" starting at index 4, so s = "dababc".
• s = "dab*abc*", remove "abc" starting at index 3, so s = "dab". Now s has no occurrences of "abc".

Example 2:

Input: s = "axxxxyyyyb", part = "xy"
Output: "ab"
Explanation: The following operations are done:

• s = "axxx*xy*yyyb", remove "xy" starting at index 4 so s = "axxxyyyb".
• s = "axx*xy*yyb", remove "xy" starting at index 3 so s = "axxyyb".
• s = "ax*xy*yb", remove "xy" starting at index 2 so s = "axyb".
• s = "a*xy*b", remove "xy" starting at index 1 so s = "ab". Now s has no occurrences of "xy".

Constraints:

• `1 <= s.length <= 1000`
• `1 <= part.length <= 1000`
• `s`​​​​​​ and `part` consists of lowercase English letters.

SOLUTION:

``````class Solution:
def removeOccurrences(self, s: str, part: str) -> str:
n = len(part)
while part in s:
i = s.index(part)
s = s[:i] + s[i+n:]
return s
``````