#include <iostream>
using namespace std;

size_t revnum(size_t res, size_t num){
    res = res + num % 10;
    if( num /= 10 )
    {
        res = res * 10;
        res = revnum(res, num);
    }
    return res;
}

int main(){
    size_t num = 12345678;
    size_t rev = 0;
    rev = revnum(rev, num);
    cout<<rev<<endl;
    return 0;
}

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