#include <iostream>
#include <string>
using namespace std;
int main() {
int n,m,ti;
    cin>>m>>n;
    if(n%m)ti=m/n+11;
    else if(!n%m)ti=m/n+10;                 
    int tot= 8*60;
    tot-=ti;if(tot<0)tot+=24*60;
    int hours=tot/60; 
    int rem=tot%60;
    printf("%02d:%02d\n",hours%24,rem);
	return 0;
}

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