Java 100% faster solution
\n Describe your approach to solving the problem. \n\n# Complexity\n- Time complexity: O(N)\n Add your time complexity here, e.g. O(n) \n\n- Space complexity: O
\n<!-- Describe your approach to solving the problem. -->\n\n# Complexity\n- Time complexity: O(N)\n<!-- Add your time complexity here, e.g. $$O(n)$$ -->\n\n- Space complexity: O(1)\n<!-- Add your space complexity here, e.g. $$O(n)$$ -->\n\n# Code\n```\nclass Solution {\n    public long findTheArrayConcVal(int[] nums) {\n        \n        long res = 0;\n        int i = 0;\n        int j= nums.length-1;\n        \n        while(i<j){\n            int num = concatenate(nums[i++],nums[j--]);\n            res += num;\n        }\n        if((nums.length&1) != 0){\n            res += nums[i];\n        }\n        return res;\n    }\n    private int concatenate(int x,int y){\n        return Integer.parseInt(String.valueOf(x)+String.valueOf(y));\n    }\n}\n```
['String', 'Bit Manipulation', 'Java']