100% Fast Easy Simple C++ Solution ✔✔
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# Co
## 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 {\npublic:\n    long long findTheArrayConcVal(vector<int>& nums) {\n        long long ans=0;\n        int i=0; int j= nums.size()-1;\n        while (i<=j){\n            if (i==j){\n                ans+= nums[i];\n                break;\n            }\n            int fir= nums[i]; int sec= nums[j];\n            int dem= nums[j];\n            int test= 0;\n            while (dem>0){test++; dem/=10;}\n            while (test--)fir*=10;\n            fir+=sec;\n            ans+= fir;\n            i++; j--;\n        }\n        return ans;\n    }\n};\n```
['Array', 'Math', 'Two Pointers', 'String', 'C++']