#include <cstdlib>
#include <iostream>

using namespace std;

int main(int argc, char *argv[])
{
    while(1){
    int y,m,d;
    int mon[12]={31,28,31,30,31,30,31,31,30,31,30,31};
    int n,N;
    cin>>y>>m>>d;
    if(y==0&&m==0&&d==0) break;
    if(y%400==0||(y%4==0&&y%100!=0))
    { mon[1]=29;
      if(y<2000||y>9999||m>12||m<1||d<1||d>29)
      cout<<-1<<endl;
      else {n=(y-1)/4-((y-1)/100-(y-1)/400);
    N=365*(y-1)+n;
    for(int i=0;i<m-1;i++)
    N+=mon[i];
    N+=d;
    switch(N%7)
    {
               case 0:cout<<7<<endl;break;
               case 1:cout<<1<<endl;break;
               case 2:cout<<2<<endl;break;
               case 3:cout<<3<<endl;break;
               case 4:cout<<4<<endl;break;
               case 5:cout<<5<<endl;break;
               case 6:cout<<6<<endl;break;
               }}}
    else{
          if(y<2000||y>9999||m>12||m<1||d<1||d>28)
          cout<<-1<<endl;
          else{
    n=(y-1)/4-((y-1)/100-(y-1)/400);
    N=365*(y-1)+n;
    for(int i=0;i<m-1;i++)
    N+=mon[i];
    N+=d;
    switch(N%7)
    {
               case 0:cout<<7<<endl;break;
               case 1:cout<<1<<endl;break;
               case 2:cout<<2<<endl;break;
               case 3:cout<<3<<endl;break;
               case 4:cout<<4<<endl;break;
               case 5:cout<<5<<endl;break;
               case 6:cout<<6<<endl;break;
               }}}}
    system("PAUSE");
    return EXIT_SUCCESS;
}
输入 年 月 日（2000<=年<=9999）求出星期几用1-7表示，输入不合理时输出-1，输入0 0 0时结束

我试过大体对了，可就是无法通过校方测试，求帮忙看是不是哪里的细节出问题了