添加（0053.最大子序和.md）：增加typescript版本

problems/0053.最大子序和.md

@@ -211,7 +211,7 @@ func maxSubArray(nums []int) int {
     return maxSum
 }
 ```
- 
+
 ### Javascript:
 ```Javascript
 var maxSubArray = function(nums) {
@@ -230,6 +230,41 @@ var maxSubArray = function(nums) {
 };
 ```
 
+### TypeScript
+
+**贪心**
+
+```typescript
+function maxSubArray(nums: number[]): number {
+    let curSum: number = 0;
+    let resMax: number = -Infinity;
+    for (let i = 0, length = nums.length; i < length; i++) {
+        curSum += nums[i];
+        resMax = Math.max(curSum, resMax);
+        if (curSum < 0) curSum = 0;
+    }
+    return resMax;
+};
+```
+
+**动态规划**
+
+```typescript
+// 动态规划
+function maxSubArray(nums: number[]): number {
+    const length = nums.length;
+    if (length === 0) return 0;
+    const dp: number[] = [];
+    dp[0] = nums[0];
+    let resMax: number = nums[0];
+    for (let i = 1; i < length; i++) {
+        dp[i] = Math.max(dp[i - 1] + nums[i], nums[i]);
+        resMax = Math.max(resMax, dp[i]);
+    }
+    return resMax;
+};
+```
+
 
 
 -----------------------