feat: add typescript solution to lc problem: No.0518.Coin Change 2 (doocs#448)

Author: zhaocchen

solution/0500-0599/0518.Coin Change 2/README.md

@@ -93,6 +93,21 @@ class Solution {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function change(amount: number, coins: number[]): number {
+    let dp = new Array(amount + 1).fill(0);
+    dp[0] = 1;
+    for (let coin of coins) {
+        for (let i = coin; i <= amount; ++i) {
+            dp[i] += dp[i - coin];
+        }
+    }
+    return dp.pop();
+};
+```
+
 ### **Go**
 
 ```go

solution/0500-0599/0518.Coin Change 2/README_EN.md

@@ -129,6 +129,21 @@ class Solution {
 }
 ```
 
+### **TypeScript**
+
+```ts
+function change(amount: number, coins: number[]): number {
+    let dp = new Array(amount + 1).fill(0);
+    dp[0] = 1;
+    for (let coin of coins) {
+        for (let i = coin; i <= amount; ++i) {
+            dp[i] += dp[i - coin];
+        }
+    }
+    return dp.pop();
+};
+```
+
 ### **Go**
 
 ```go

solution/0500-0599/0518.Coin Change 2/Solution.ts

@@ -0,0 +1,10 @@
+function change(amount: number, coins: number[]): number {
+    let dp = new Array(amount + 1).fill(0);
+    dp[0] = 1;
+    for (let coin of coins) {
+        for (let i = coin; i <= amount; ++i) {
+            dp[i] += dp[i - coin];
+        }
+    }
+    return dp.pop();
+};