Create manacher.cpp

PNU-PULSE · Jul 29, 2024 · 51b5e10 · 51b5e10
1 parent c46b498
commit 51b5e10
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/ps/string/manacher/manacher.cpp b/ps/string/manacher/manacher.cpp
@@ -0,0 +1,9 @@
+//ref: https://www.crocus.co.kr/1075
+void manachers(string st, int n){
+    int r = 0, p = 0;
+    for (int i = 0; i < n; i++){
+        arr[i] = (i <= r) ? min(arr[2 * p - i], r - i) : 0;
+        while (i - arr[i] - 1 >= 0 && i + arr[i] + 1 < n && st[i - arr[i] - 1] == st[i + arr[i] + 1]) ++arr[i];
+        if (r < i + arr[i])  r = i + arr[i], p = i;
+    }
+}