HDU 1234 开门人和关门人

#include <stdio.h>
#include <string.h>
int main()
{
bool judge(char t1[],char t2[]);
char id[20];
char t1[20];
char t2[20];
char ans1[20];
char ans2[20];
char time1[20];
char time2[20];
int n;
int m;
scanf("%d",&n);
while(n--)
{
memset(time1,'\0',sizeof(time1));
memset(time2,'\0',sizeof(time2));
scanf("%d",&m);
while(m--)
{

scanf("%s%s%s",id,t1,t2);
if(judge(t1,time1))
{
strcpy(time1,t1);
strcpy(ans1,id);
}
if(judge(time2,t2))
{
strcpy(time2,t2);
strcpy(ans2,id);
}

}
printf("%s %s\n",ans1,ans2);
}
return 0;
}

bool judge(char t1[],char t2[])    //判断t1是否早于t2
{
int len1=strlen(t1);
int len2=strlen(t2);
if(len1==0||len2==0)
return true;
if(strcmp(t1,t2)<0)
return true;
else
return false;
}