#include<stdio.h>
int main(){
    int s,v,t;
    scanf("%d%d",&s,&v);
    t=int(s/v)+10+s%v;
    if(int(t/60)>=8)
        if((60-t%60)<10)    
            printf("%d:0%d",32-int(t/60),60-t%60);
        else  
            printf("%d:%d",32-int(t/60),60-t%60);
    else
        if((60-t%60)<10)
            printf("0%d:0%d",7-int(t/60),60-t%60);
        else
            printf("0%d:%d",7-int(t/60),60-t%60);
}