一个含有字符串的数组，例如["a","b","a","c","b","d","a","1","1"]需要得到一个新数组 ["a1","b1","a2","c","b2","d","a3","11","12"]

以下是Python代码实现：

def combine_strings(arr):
    counts = {}
    new_arr = []
    for string in arr:
        if string in counts:
            counts[string] += 1
            new_arr.append(string + str(counts[string]))
        else:
            counts[string] = 1
            new_arr.append(string)

    return new_arr

代码思路：

1. 创建一个空字典counts，用于记录每个字符串出现的次数。
2. 遍历原始数组中的每个字符串。
3. 如果当前字符串已经在counts字典中，则将其出现次数加1，并将其拼接成新字符串添加到新数组中。
4. 如果当前字符串不在counts字典中，则将其添加到counts字典中，并直接将其添加到新数组中。
5. 返回新数组。

例如，对于输入数组["a","b","a","c","b","d","a","1","1"]，counts字典的值会变化如下：

| 字符串 | 出现次数 |
| ---- | ---- |
| a | 1 |
| b | 1 |
| c | 1 |
| d | 1 |
| 1 | 1 |
| a | 2 |
| 1 | 2 |

最终，新数组的值为["a1","b1","a2","c","b2","d","a3","11","12"]。