1844. Replace All Digits with Characters ¶ Time: $O(n)$ Space: $O(n)$ C++JavaPython 1 2 3 4 5 6 7 8class Solution { public: string replaceDigits(string s) { for (int i = 0; i < s.length(); ++i) s[i] += s[i - 1] - '0'; return s; } }; 1 2 3 4 5 6 7 8 9 10class Solution { public String replaceDigits(String s) { char[] A = s.toCharArray(); for (int i = 1; i < A.length; i += 2) A[i] += (char) (A[i - 1] - '0'); return String.valueOf(A); } } 1 2 3 4 5 6 7 8class Solution: def replaceDigits(self, s: str) -> str: chars = list(s) for i in range(1, len(chars), 2): chars[i] = chr(ord(chars[i - 1]) + ord(chars[i]) - ord('0')) return ''.join(chars)