#include<stdio.h>
#include<stdlib.h>
int main(int argc, char const *argv[]){
	char s[6];
	int h,m;
	scanf("%s",s);
	h=(s[0]-'0')*10+(s[1]-'0');
	m=(s[3]-'0')*10+(s[4]-'0');
	m+=5;
	if(m>59){
		m-=60;
		h++;
		if(h>23) h=0;
	}
	printf("%02d:%02d\n",h,m);
	return 0;
}