Merge pull request #1271 from xiaofei-2020/dp04

添加(0746.使用最小花费爬楼梯.md)：增加typescript版本

problems/0746.使用最小花费爬楼梯.md

@@ -266,7 +266,30 @@ var minCostClimbingStairs = function(cost) {
 };
 ```
 
+### TypeScript
+
+```typescript
+function minCostClimbingStairs(cost: number[]): number {
+    /**
+        dp[i]: 走到第i阶需要花费的最少金钱
+        dp[0]: cost[0];
+        dp[1]: cost[1];
+        ...
+        dp[i]: min(dp[i - 1], dp[i - 2]) + cost[i];
+     */
+    const dp: number[] = [];
+    const length: number = cost.length;
+    dp[0] = cost[0];
+    dp[1] = cost[1];
+    for (let i = 2; i <= length; i++) {
+        dp[i] = Math.min(dp[i - 1], dp[i - 2]) + cost[i];
+    }
+    return Math.min(dp[length - 1], dp[length - 2]);
+};
+```
+
 ### C
+
 ```c
 int minCostClimbingStairs(int* cost, int costSize){
     //开辟dp数组，大小为costSize