#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define loop(i,a,b) for(i=a;i<b;i++)
#define rloop(i,a,b) for(i=a;i>=b;i--)
#define vi vector<int>
#define vl vector<ll>
#define vii vector< vector<int> >
#define vll vector< vector<ll> >
#define vs vector<string>
#define pii pair<int,int>
#define psi pair<string,int>
#define pis pair<int,string>
#define pss pair<string,string>
const int inf=1000000001;
const ll INF=1e16;
#define MOD 1000000007
#define mod 1000000009
#define pi 3.14159265358979323846
#define Sp(p) cout<<setprecision(15)<<fixed<<p<<endl;
#define N 30
#define T 4001
int n,t;
vi l(N);
vector<psi> sub(N);
vi rank(N,0);
vii ans(T,vi(N,0));


int main(){
  string t;
  cin>>t;
  int h=(t[0]-'0')*10+t[1]-'0';
  int m=(t[3]-'0')*10+t[4]-'0';
  m+=5;
  if(m>=60){
    m-=60;
    h++;
  }
  if(h>=24){
    h-=24;
  }
  printf("%02d:%02d\n",h,m);
}