URAL 1969. Hong Kong Tram

有一个trick就是没想到，枚举第二段时间后，要检测该火车能否继续跑一圈来判断，不能先检测前半圈能不能跑加进去后在检测后半段；

// **** 部分不能放在那个位置；

最近代码导致的错误总是找不出，贴下代码权当提醒吧！！

 #include<cstdio>
 #include<cstring>
 #include<iostream>
 #include<cmath>
 #include<cstdlib>
 #include<vector>
 #include<algorithm>
 using namespace std;
 int us[];
 int ID[];
 vector<int> pr[];
 int ti[];
 int n;
 void FIND(int i,int x,int nn,int y){
     int pt = ti[i] - x;
     pr[nn].clear();
     pr[nn].push_back(ti[i] - x);
     while ( true )
     {
         int nt = pt + x;
         if ( ID[nt] == - ) break;
         us[nt] = ;
        //  pr[nn].push_back(pt + x + y); ****
         nt = nt + y + y;
         if (ID[nt] == -) break;
         us[nt] = ;

         pr[nn].push_back(pt + x + y);
         pr[nn].push_back(pt + x + y + y + x);
         pt = pt + y *  + x + x;
     }
 }
 int work(int x,int y) {
     memset(us, , sizeof us);
     pr[].clear();
     int mm = ;
     us[ti[]] = ;
     FIND(,x,,y);
     int nn = ;
     mm = pr[].size();
     if ( (mm - ) %  ) return ;
     for ( int i = ; i < n; i ++ )
     {
         if ( us[ti[i]] ) continue;
         us[i] = ;
         FIND(i,x,nn,y);
         nn ++;
         if ( pr[nn-].size() != mm ) return false;
     }
      if (pr[][] <= pr[nn-][]) return ;

     for (int i = ; i < nn; i++) {
         int sz = pr[i].size();
         for (int j = ; j < sz; j++) {
             int hh,mm,ss;
             hh = pr[i][j] / ;
             mm = pr[i][j] %  / ;
             ss = pr[i][j] %  % ;
             printf("%02d:%02d:%02d%c",hh,mm,ss, j == sz- ? '\n':' ');
         }
     }
     return ;
 }
 void solve(){
     for (int k = ; k < n; k++) {
         int tx = ti[] - ti[], ty = ti[k] - ti[];
         if (ty % ) continue;
         if (work(tx,ty/)) return;
     }
   //  cout<<" ** "<< endl;
 }
 int main(){
    // freopen("in.txt","r",stdin);
     n = ;
     int hh,mm,ss;
     memset(ID,-,sizeof(ID));
     while (~scanf("%d:%d:%d",&hh,&mm,&ss)) {
         ti[n++] = hh *  + mm *  + ss;
         ID[ti[n-]] = n-;
     }
    // cout<<" ** "<<endl;
     solve();
     return ;
 }