Create: 1888-minimum-number-of-flips-to-make-the-binary-string-alternating.js

Author: nickap

javascript/1888-minimum-number-of-flips-to-make-the-binary-string-alternating.js

@@ -0,0 +1,36 @@
+/**
+ * https://leetcode.com/problems/minimum-number-of-flips-to-make-the-binary-string-alternating/
+ * Time O(n), Space O(1)
+ * @param {string} s
+ * @return {number}
+ */
+var minFlips = (s) => {
+    if (!s || s.length < 1) return 0;
+
+    const initialLen = s.length;
+    if (initialLen % 2 === 1) s += s;
+
+    let evenCmp = 0;
+    let oddCmp = 0;
+    let result = Infinity;
+    let end = 0;
+    let start = 0;
+
+    while (end < s.length) {
+        if (end % 2 !== Number(s[end])) evenCmp++;
+        if ((end % 2 ^ 1) !== Number(s[end])) oddCmp++;
+
+        if (end >= initialLen) {
+            if (start % 2 !== Number(s[start])) evenCmp--;
+            if ((start % 2 ^ 1) !== Number(s[start])) oddCmp--;
+            start++;
+        }
+
+        if (end >= initialLen - 1) {
+            result = Math.min(evenCmp, oddCmp, result);
+        }
+        end++;
+    }
+
+    return result;
+};