feat: add js solution to lc problem: No.2029

Author: rain84

solution/2000-2099/2029.Stone Game IX/README.md

@@ -225,6 +225,30 @@ function stoneGameIX(stones: number[]): boolean {
 }
 ```
 
+#### JavaScript
+
+```js
+function stoneGameIX(stones) {
+    const c1 = Array(3).fill(0);
+    for (const x of stones) {
+        ++c1[x % 3];
+    }
+    const c2 = [c1[0], c1[2], c1[1]];
+    const check = cnt => {
+        if (--cnt[1] < 0) {
+            return false;
+        }
+        let r = 1 + Math.min(cnt[1], cnt[2]) * 2 + cnt[0];
+        if (cnt[1] > cnt[2]) {
+            --cnt[1];
+            ++r;
+        }
+        return r % 2 === 1 && cnt[1] !== cnt[2];
+    };
+    return check(c1) || check(c2);
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

solution/2000-2099/2029.Stone Game IX/README_EN.md

@@ -218,6 +218,30 @@ function stoneGameIX(stones: number[]): boolean {
 }
 ```
 
+#### JavaScript
+
+```js
+function stoneGameIX(stones) {
+    const c1 = Array(3).fill(0);
+    for (const x of stones) {
+        ++c1[x % 3];
+    }
+    const c2 = [c1[0], c1[2], c1[1]];
+    const check = cnt => {
+        if (--cnt[1] < 0) {
+            return false;
+        }
+        let r = 1 + Math.min(cnt[1], cnt[2]) * 2 + cnt[0];
+        if (cnt[1] > cnt[2]) {
+            --cnt[1];
+            ++r;
+        }
+        return r % 2 === 1 && cnt[1] !== cnt[2];
+    };
+    return check(c1) || check(c2);
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

solution/2000-2099/2029.Stone Game IX/Solution.js

@@ -0,0 +1,19 @@
+function stoneGameIX(stones) {
+    const c1 = Array(3).fill(0);
+    for (const x of stones) {
+        ++c1[x % 3];
+    }
+    const c2 = [c1[0], c1[2], c1[1]];
+    const check = cnt => {
+        if (--cnt[1] < 0) {
+            return false;
+        }
+        let r = 1 + Math.min(cnt[1], cnt[2]) * 2 + cnt[0];
+        if (cnt[1] > cnt[2]) {
+            --cnt[1];
+            ++r;
+        }
+        return r % 2 === 1 && cnt[1] !== cnt[2];
+    };
+    return check(c1) || check(c2);
+}