给定一个字符串 s,检查它是否可以通过将其的子字符串和添加多个副本的子字符串一起构建. C++解决方案是?
Here's a possible C++ implementation for the task:

```
bool repeatedSubstringPattern(string s) {
    int n = s.size();
    for(int len = 1; len <= n/2; len++) {
        if(n % len == 0) {
            string sub = s.substr(0, len);
            int k = len;
            while(k < n && s.substr(k, len) == sub) {
                k += len;
            }
            if(k == n) {
                // substring s[0, len-1] can be repeated
                return true;
            }
        }
    }
    return false;
}
```

The function takes a string `s` as input and returns a boolean value indicating whether `s` can be constructed by taking a substring of it and appending multiple copies of the substring together.

The function loops through all possible substring lengths `len` from 1 to `n/2`, where `n` is the length of `s`. For each length `len`, it checks if `n` is a multiple of `len`, so that we can form repeated copies of the substring.

If `n` is a multiple of `len`, we extract the first `len` characters of `s` as the substring `sub`. We then iterate over the rest of `s` in chunks of length `len`, checking if each chunk matches `sub`. If all chunks match `sub`, we have found a repeating substring of length `len`, and we return true.

If no repeating substring is found, we return false.