hdu1036

#include<stdio.h>
int main()
{
int n;
double d;
int num;
char h,m1,m2,s1,s2;
scanf("%d",&n);
scanf("%lf",&d);
while(scanf("%d",&num)!=EOF)
{

printf("%3d: ",num);
bool flag=true;
int sumtime=0;
for(int i=0;i<n;i++)
{getchar();
scanf("%c:%c%c:%c%c",&h,&m1,&m2,&s1,&s2);
if(h=='-') flag=false;
if(flag==false)continue;
sumtime+=(h-'0')*3600+((m1-'0')*10+(m2-'0'))*60+(s1-'0')*10+(s2-'0');
}
if(flag==false)printf("-\n");
else
{
double t1=sumtime/d;
int t2=(int)(t1+0.5);
printf("%d:%02d min/km\n",t2/60,t2%60);

}
}
return 0;
}