feat: add typescript solution to lc problem: No.1346.Check If N and Its Double Exist

Author: zhaocchen

Diff for: solution/1300-1399/1346.Check If N and Its Double Exist/README.md

@@ -91,6 +91,25 @@ class Solution {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function checkIfExist(arr: number[]): boolean {
+    for (let i = arr.length - 1; i >= 0; --i) {
+        let cur = arr[i];
+        let t1 = 2 * cur; 
+        if (arr.includes(t1) && arr.indexOf(t1) != i) {
+            return true;
+        }
+        let t2 = cur >> 1;
+        if (cur % 2 == 0 && arr.includes(t2) && arr.indexOf(t2) != i) {
+            return true;
+        }
+    }
+    return false;
+};
+```
+
 ### **C++**
 
 ```cpp

Diff for: solution/1300-1399/1346.Check If N and Its Double Exist/README_EN.md

@@ -84,6 +84,25 @@ class Solution {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function checkIfExist(arr: number[]): boolean {
+    for (let i = arr.length - 1; i >= 0; --i) {
+        let cur = arr[i];
+        let t1 = 2 * cur; 
+        if (arr.includes(t1) && arr.indexOf(t1) != i) {
+            return true;
+        }
+        let t2 = cur >> 1;
+        if (cur % 2 == 0 && arr.includes(t2) && arr.indexOf(t2) != i) {
+            return true;
+        }
+    }
+    return false;
+};
+```
+
 ### **C++**
 
 ```cpp

Diff for: solution/1300-1399/1346.Check If N and Its Double Exist/Solution.ts

@@ -0,0 +1,14 @@
+function checkIfExist(arr: number[]): boolean {
+    for (let i = arr.length - 1; i >= 0; --i) {
+        let cur = arr[i];
+        let t1 = 2 * cur; 
+        if (arr.includes(t1) && arr.indexOf(t1) != i) {
+            return true;
+        }
+        let t2 = cur >> 1;
+        if (cur % 2 == 0 && arr.includes(t2) && arr.indexOf(t2) != i) {
+            return true;
+        }
+    }
+    return false;
+};