#include<cstdio>


int main(void)
{
	int h, m;

	while(scanf("%d:%d", &h, &m)==2)
	{
		m=h*60+m+5;
		h=(m/60)%24;
		m%=60;
		printf("%02d:%02d\n", h, m);
	}

	return 0;
}