#include <iostream>
#include <cstring>
using namespace std;

int main()
{
  const char *s;
  string str;
  char *found;

  cout << "Enter a string: ";
  cin >> str;

  s = str.c_str();

  found = strchr(s, 'a');
  cout << "strchr(\"" << s << "\", 'a') returned ";
  if (found == NULL) {         // -OR-  if (!found) ...
    cout << "NULL\n";
  } else {
    cout << '"' << found << '"' << endl;
  }

  found = strrchr(s, 'a');
  cout << "strrchr(\"" << s << "\", 'a') returned ";
  if (!found) {   
    cout << "NULL\n";
  } else {
    cout << '"' << found << '"' << endl;
  }

  found = strstr(s, "ba");
  cout << "strstr(\"" << s << "\", \"ba\") returned ";
  if (found == NULL) {
    cout << "NULL\n";
  } else {
    cout << '"' << found << '"' << endl;
  }
  return 0;
}