#include<stdio.h>
int main()
{
    int s,v,h;
    float m;
    scanf("%d%d",&s,&v);
    m=s*1.0/v;
    m+=10;
    h=m/60;
    m=m-h*60;
    h=7-h;
    if(h<=0)
    h+=24;
    if(m-int(m)>0)
    m=59-int(m);
    else
    m=60-int(m);
    if(h<10)
    printf("0%d",h);
    else
    printf("%d",h);
    printf(":");
    if(m<10)
    printf("0%d",int(m)); 
    else
    printf("%d",int(m));
    return 0;       
}