Easy C++  Solution
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```cpp []\nclass Solution {\npublic:\n    string modifyString(string s) {\n        string word="";\n        int n=s.length();\n        for(int i=0;i<n;i++){\n            while(i<n && s[i]!=\'?\') {\n                word+=s[i];\n                i++;\n            }\n            if(s[i]==\'?\'){\n                char left=i>0?word.back():\' \';\n                char right=i+1<n?s[i+1]:\' \';\n                cout<<left<<" "<<right<<endl;\n                for(char ch=\'a\';ch<=\'z\';ch++){\n                    if(ch==left || ch==right) continue;\n                    else{\n                        word+=ch;\n                        break;\n                    }\n                }\n            }\n        }\n        return word;\n    }\n};\n```
['C++']