蓝桥杯 黑色星期五

#include<iostream>

using namespace std;
int main(int argc, char **argv) {
  int y;
  cin>>y;

  int  days[13]= {0,31,28,31,30,31,30,31,31,30,31,30,31};  
  if(y%400==0||y%4==0&&y%100!=0)
	days[2]=29;
  
  int week=4;

  for(int i=1;i<=12;++i) {
	int sum=0;
	for(int j=1;j<i;++j){
	  sum+=days[j];
	}
	
	sum+=13;
	if((sum+(7-week))%7==5)
	  cout<<"y-"<<y<<"-"<<i<<endl;
  }

  return 0;
}