string::compare

strcmp와 같이 참이라면 0을 리턴한다. strncmp와 같은 함수로 정의하고 싶으면 compare(시작 인덱스, 비교할 길이, 비교할 대상)으로 나타낼 수 있다

 

// comparing apples with apples
/* 출처
http://www.cplusplus.com/reference/string/string/compare/
*/

#include <iostream>
#include <string>

int main ()
{
  std::string str1 ("green apple");
  std::string str2 ("red apple");

  if (str1.compare(str2) != 0)
    std::cout << str1 << " is not " << str2 << '\n';

  if (str1.compare(6,5,"apple") == 0)
    std::cout << "still, " << str1 << " is an apple\n";

  if (str2.compare(str2.size()-5,5,"apple") == 0)
    std::cout << "and " << str2 << " is also an apple\n";

  if (str1.compare(6,5,str2,4,5) == 0)
    std::cout << "therefore, both are apples\n";

  return 0;
}