Create 301-remove-invalid-parentheses.js

Author: everthis

301-remove-invalid-parentheses.js

@@ -0,0 +1,35 @@
+/**
+ * @param {string} s
+ * @return {string[]}
+ */
+const removeInvalidParentheses = function(s) {
+  const ans = [];
+  remove(s, ans, 0, 0, ["(", ")"]);
+  return ans;
+};
+
+function remove(s, ans, last_i, last_j, par) {
+  for (let stack = 0, i = last_i; i < s.length; i++) {
+    if (s.charAt(i) === par[0]) stack++;
+    if (s.charAt(i) === par[1]) stack--;
+    if (stack >= 0) continue;
+    for (let j = last_j; j <= i; j++) {
+      if (
+        s.charAt(j) === par[1] &&
+        (j === last_j || s.charAt(j - 1) != par[1])
+      ) {
+        remove(s.slice(0, j) + s.slice(j + 1), ans, i, j, par);
+      }
+    }
+    return;
+  }
+  const reversed = s
+    .split("")
+    .reverse()
+    .join("");
+  if (par[0] === "(") {
+    remove(reversed, ans, 0, 0, [")", "("]);
+  } else {
+    ans.push(reversed);
+  }
+}