#include <stdio.h>
int main(void){
	char t[6];
	scanf("%s",t);
	int h=(t[0]-'0')*10+(t[1]-'0');
	int m=(t[3]-'0')*10+(t[4]-'0');
	m+=5;
	if(m>59){m-=60;h+=1;}
	if(h>23) h-=24;
	printf("%02d:%02d",h,m);
	return 0;
}