Simple java solution
Complexity\n- Time complexity: O(n)\n\n- Space complexity: O(1)\n\n# Code\n\nclass Solution {\n    public int removeAlmostEqualCharacters(String word) {\n      
# Complexity\n- Time complexity: $$O(n)$$\n\n- Space complexity: $$O(1)$$\n\n# Code\n```\nclass Solution {\n    public int removeAlmostEqualCharacters(String word) {\n        int count=0;\n        for(int i=0;i<word.length()-1;)\n        {\n            char c=word.charAt(i);\n            char d=word.charAt(i+1);\n            if(c==d || (c+1)==d || (c-1)==d)\n            {\n                count++;\n                i+=2;\n            }\n            else\n            {\n                i++;\n            }\n        }\n        return count;\n    }\n}\n```
['Java']