#include <iostream>
using namespace std;
int main(){
const char* str;
str = "\0"; // or str = 0;
cout << str << endl;
cerr << "str points to: " << (int)str << endl;
cerr << cout.bad() << endl;
cerr << cout.eof() << endl;
cerr << cout.fail() << endl;
cout << "Welcome" << endl;
return 0;
}
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