#include <iostream>
#include <string>

using namespace std;

bool CheckingNumbers(const string&);

int main() {

    setlocale(LC_ALL, "rus");

    string s1 = "123";
    string s2 = "asd";
    string s3 = "123asd";
    string s4 = "asd123";

    cout << CheckingNumbers(s1) << endl;
    cout << CheckingNumbers(s2) << endl;
    cout << CheckingNumbers(s3) << endl;
    cout << CheckingNumbers(s4) << endl;


        return 0;
}

bool CheckingNumbers(const string& s) {
    bool b = true;
    for (auto& a : s) {
        if (!iswalnum(a)) {
            b = false;
            break;
        }
    }
    return b;
};

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