#include <stdio.h> #include <math.h>

int main(int argc, char *argv[]) {

int s,v,time,a,b1;
scanf("%d%d",&s,&v);
time=8*60-(ceil(s*1.0/v)+10);
a=time/60;
b=time%60;
printf("0%d:%d",a,b);
return 0;

}