C언어] 올해가 윤년인지 평년인지 판단 예제; Current Year is Leap Year?

#include <stdio.h>
#include <time.h>

int isLeapYear(int year);
int getCurrentYear(void);


int main(void) {

  int cyear = getCurrentYear();

  printf("올해는 %d 년입니다.\n", cyear);

  if (isLeapYear(cyear)) {
    puts("윤년입니다");
  } else {
    puts("평년입니다");
  }

  return 0;
}




int isLeapYear(int year) {
  if (year % 4)   return 0;
  if (year % 100) return 1;
  if (year % 400) return 0;

  return 1;
}


int getCurrentYear(void) {
  time_t timer;
  struct tm *t;

  timer = time(NULL);
  t = localtime(&timer);

  return t->tm_year + 1900;
}