Permutation in String
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Topic refresher: Sliding Window — Live Range
Maintain [L,R] that satisfies a constraint; answer from length/sum/counts.
int L = 0;
for (int R = 0; R < n; R++) {
// add s[R]
while (/* invalid */) { /* remove s[L] */ L++; }
// update answer
}MediumSliding WindowLeetCode #567
Permutation in String
Fixed window of len(s1). Compare frequency maps / matches count.
Examples
Example 1
Input
ab eidbaooo
Output
true
Example 2
Input
ab eidboaoo
Output
false
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