#include<iostream>
using namespace std;
int main()
{
string s;
cin >> s;
int h = (s[0]-'0')*10+(s[1]-'0');
int m = (s[3]-'0')*10+(s[4]-'0');
if(m<=54){
printf("%2d:%2d\n",h,m+5);
}else{
printf("%2d:%2d\n",(h+1)%24,(m+5)%60);
}
}