simple and understandable , few line code , PYTHON
Intuition\n Describe your first thoughts on how to solve this problem. \n\n# Approach\n Describe your approach to solving the problem. \n\n# Complexity\n- Time 
# Intuition\n<!-- Describe your first thoughts on how to solve this problem. -->\n\n# Approach\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity:\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity:\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass Solution:\n    def minimumSum(self, nums: List[int]) -> int:\n\n        minn=sum(nums)*sum(nums)\n        new=minn\n\n        for i in range(len(nums)):\n            for j in range(i+1,len(nums)):\n                for k in range(j+1,len(nums)):\n                    if minn > nums[i] + nums[j] + nums[k] and (nums[i] < nums[j] and nums[k] < nums[j]):\n                        minn =  nums[i] + nums[j] + nums[k]\n        if minn==new:\n            return -1\n        else:\n            return minn\n```
['Python3']