add: 每个元音包含偶数次的最长子字符串

src/string/find-the-longest-substring-containing-vowels-in-even-counts.js

@@ -0,0 +1,30 @@
+/**
+ * @param {string} s
+ * @return {number}
+ */
+export const findTheLongestSubstring = function (s) {
+  const n = s.length
+  const pos = new Array(1 << 5).fill(-1)
+  let ans = 0; let status = 0
+  pos[0] = 0
+  for (let i = 0; i < n; ++i) {
+    const ch = s.charAt(i)
+    if (ch === 'a') {
+      status ^= 1 << 0
+    } else if (ch === 'e') {
+      status ^= 1 << 1
+    } else if (ch === 'i') {
+      status ^= 1 << 2
+    } else if (ch === 'o') {
+      status ^= 1 << 3
+    } else if (ch === 'u') {
+      status ^= 1 << 4
+    }
+    if (~pos[status]) {
+      ans = Math.max(ans, i + 1 - pos[status])
+    } else {
+      pos[status] = i + 1
+    }
+  }
+  return ans
+}