Merge pull request #1401 from xiaofei-2020/extra03

添加（1207.独一无二的出现次数.md）：增加typescript版本

problems/1207.独一无二的出现次数.md

@@ -150,5 +150,39 @@ var uniqueOccurrences = function(arr) {
 };
 ```
 
+TypeScript：
+
+> 借用数组：
+
+```typescript
+function uniqueOccurrences(arr: number[]): boolean {
+    const countArr: number[] = new Array(2001).fill(0);
+    for (let i = 0, length = arr.length; i < length; i++) {
+        countArr[arr[i] + 1000]++;
+    }
+    const flagArr: boolean[] = new Array(1001).fill(false);
+    for (let count of countArr) {
+        if (count === 0) continue;
+        if (flagArr[count] === true) return false;
+        flagArr[count] = true;
+    }
+    return true;
+};
+```
+
+> 借用map、set
+
+```typescript
+function uniqueOccurrences(arr: number[]): boolean {
+    const countMap: Map<number, number> = new Map();
+    arr.forEach(val => {
+        countMap.set(val, (countMap.get(val) || 0) + 1);
+    })
+    return countMap.size === new Set(countMap.values()).size;
+};
+```
+
+
+
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