abba accepted !!! Ganapati Bappa Morya ,Mangal Murthi Morya !!!!! :D
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\n        if(s[0]==\'?\')\n        {\n            int b=s[1];\n\n             for(int j=97;j<=122;j++)\n            {\n                if(j!=b)\n                  {\n                    s[0]=char(j);\n                    break;\n                  }\n                j++;\n            }\n        }\n\n        if(s[s.length()-1]==\'?\')\n        {\n             int a=int(s[s.length()-1-1]);\n\n             for(int j=97;j<=122;j++)\n            {\n                if(j!=a)\n                  {\n                    s[s.length()-1]=char(j);\n                    break;\n                  }\n                j++;\n            }\n\n        }\n\n\n        for(int i=1;i<s.length()-1;i++)\n        {\n            if(s[i]==\'?\')\n            {\n            int a=int(s[i-1]);\n            int b=int(s[i+1]);\n\n            for(int j=97;j<=122;j++)\n            {\n                if(j!=a&&j!=b)\n                  {\n                    s[i]=char(j);\n                    break;\n                  }\n                j++;\n            }\n            }\n        }\n\n\n              return s;\n    }\n};\n```
['C++']