#include <iostream>
#include <string>
#include <sstream>
#include <algorithm>
using namespace std;
 
string replace_num_with_x(const string &str);
 
int main() {
    cout << "Please enter a line of text:";
    string str;
    getline(cin, str);
    cout << replace_num_with_x(str);
}
 
string replace_num_with_x(const string &str) {
    istringstream str_strm(str);
    ostringstream out_strm;
    string word;
 
    if (str_strm >> word) {
		do {
			if (word.find_first_not_of("0123456789") == string::npos) {
            	fill(word.begin(), word.end(), 'x');
	        }
	        out_strm << word;
			if (!(str_strm >> word)) break;
			out_strm << ' ';
    	}
    	while (true);
    }
 
    return out_strm.str();
}

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

TXkgdXNlcklEIGlzIGpvaG4xNyBhbmQgbXkgNCBkaWdpdCBwaW4gaXMgMTIzNCB3aGljaCBpcyBzZWNyZXQ=

My userID is john17 and my 4 digit pin is 1234 which is secret