杭电 ACM 1084,该如何解决

杭电 ACM 1084
http://acm.hdu.edu.cn/showproblem.php?pid=1084  

下面是我的代码 不知WA的 原因 

#include <iostream>
#include <string.h>
using namespace std;

struct stu
{
  int p ;
  char time[20];  
  int grade;
  int rank;
};


char min4[20],min3[20],min2[20],min1[20];//用来记录最短时间

void GetMin(stu* student);

int main()
{
  struct stu TheStu[100];
  int StuNumber;  
  int i ,j,k,m,n;  

   
  while( cin>>StuNumber ,StuNumber > 0 )
  {


  for ( i = 0 ; i< StuNumber ; i++)
  {
  j=0 , k=0, m =0, n = 0;
  cin>>TheStu[i].p>>TheStu[i].time;//input

  strcpy(min4,"AAAAAAAAAAAA");
  strcpy(min3,"AAAAAAAAAAAA");
  strcpy(min2,"AAAAAAAAAAAA");
  strcpy(min1,"AAAAAAAAAAAA");  


  //set grage if p = 0 or p = 5 

  if ( TheStu[i].p == 5)
  {
  TheStu[i].grade = 100;
  }

  if ( TheStu[i].p == 0 )
  {
  TheStu[i].grade = 50;
  }

  if ( TheStu[i].p == 4 )
  {
  TheStu[i].rank = n ++;  
  GetMin(&TheStu[i]);
  }

  if ( TheStu[i].p == 3 )
  {
  TheStu[i].rank = m ++;
  GetMin(&TheStu[i]);
  }

  if ( TheStu[i].p == 2)
  {
  TheStu[i].rank = k ++;
  GetMin(&TheStu[i]);
  }

  if ( TheStu[i].p == 1 )
  {
  TheStu[i].rank = j ++;
  GetMin(&TheStu[i]);
  }
   
  }  

  for ( i = 0 ; i< StuNumber ; i++)
  {
  if ( TheStu[i].p == 5 || TheStu[i].p == 0 )
  {
  cout<<TheStu[i].grade<<endl;
  }  
   
   
  if ( TheStu[i].p == 4 )
  {
  if ( TheStu[i].rank <= n/2 && strcmp(TheStu[i].time , min4) <= 0 )
  {
  TheStu[i].grade = 95 ;
  }
  else
  {
  TheStu[i].grade = 90 ;
  }

  cout<<TheStu[i].grade<<endl;
   
  }

   
  if ( TheStu[i].p == 3 )
  {
  if ( TheStu[i].rank <= n/2 && strcmp(TheStu[i].time , min3) <= 0 )
  {
  TheStu[i].grade = 85 ;
  }
  else
  {
  TheStu[i].grade = 80 ;
  }
   
  cout<<TheStu[i].grade<<endl;
  }

   
  if ( TheStu[i].p == 2)
  {
  if ( TheStu[i].rank <= n/2 && strcmp(TheStu[i].time , min2) <= 0 )
  {
  TheStu[i].grade = 75 ;
  }
  else
  {
  TheStu[i].grade = 70 ;
  }
   
  cout<<TheStu[i].grade<<endl;
  }

   
  if ( TheStu[i].p == 1 )
  {
  if ( TheStu[i].rank <= n/2 && strcmp(TheStu[i].time , min1) <= 0 )
  {
  TheStu[i].grade = 65 ;
  }
  else
  {
  TheStu[i].grade = 60 ;
  }
   
  cout<<TheStu[i].grade<<endl;
  }

  if ( i == StuNumber - 1 )
  {
  cout<<endl;
  }
   
  }//for

   

  }//while

  return 0 ;
}



void GetMin(stu* student)
{
  if ( student->p == 4 )
  {
  if ( strcmp(student->time,min4) < 0) //输入时间更短
  {
  strcpy(min4,student->time);
  }  
   
  }
  else
  if ( student->p == 3 )
  {
  if ( strcmp(student->time,min3) < 0) //输入时间更短
  {
  strcpy(min3,student->time);
  }  
   

  }
  else
  if ( student->p == 2 )
  {
   
  if ( strcmp(student->time,min2) < 0) //输入时间更短
  {
  strcpy(min2,student->time);
  }  
   
  }

  else
  {

  if ( strcmp(student->time,min1) < 0) //输入时间更短
  {
  strcpy(min1,student->time);
  }  

  }
}

[解决办法]
参考下这个：
http://hi.baidu.com/qiaolw/item/7268d718d71b084a6926bb15