class Solution { public: string modifyString(string s) { string alphabets="abcdefghijklmnopqrstuvwxyz"; char chr; for(int i=0;i0 && i0){ while(chr==s[i-1]){ chr=alphabets[rand()%26]; } }else{ while(chr==s[i+1]){ chr=alphabets[rand()%26]; } } s[i]=chr; } } return s; } };