------
## 最终结论
```python
from collections import Counter

def find_Sum(arr, target):
    count = Counter(arr)
    repeated_elements = [num for num, freq in count.items() if freq > 1]
    return sum(repeated_elements)

# Test cases
assert find_Sum([1,2,3,1,1,4,5,6],8) == 3
assert find_Sum([1,2,3,1,1],5) == 3
assert find_Sum([1,1,2],3) == 2
```