leet202568..cpp

class Solution {
public:
    int minMaxDifference(int num) {
        string str = to_string(num);
        string ma = "";
        string mi = "";
        int n = str.size();
        char ele = ' ';
        // Step 1: Find first non-9 digit for max replacement
        for(int i=0;i<n;i++){
            if(str[i] != '9'){
                ele = str[i];
                break;
            }
        }
        // Step 2: Replace that digit with 9 for max
        for(int i=0;i<n;i++){
            if(ele == str[i]) ma += '9';
            else ma += str[i];
        }
        // Step 3: Replace first digit for min with 0
        for(int i=0;i<n;i++){
            if(str[0] == str[i]) mi += '0';
            else mi += str[i];
        }
        // Step 4: Convert and calculate result
        return stoi(ma) - stoi(mi);
    }
};