#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("Yes");}else{puts("No");}
#define MAX_N 200005

int main() {
    string s;
    cin >> s;
    int h = 0, m = 0;
    h = (s[0] - '0') * 10 + s[1] - '0';
    m = (s[3] - '0') * 10 + s[4] - '0';
    m += 5;
    if(m >= 60){
        h++;
        m %= 60;
    }
    if(h == 24)h = 0;
    cout << setfill('0') << right << setw(2) << h;
    cout << ':';
    cout << setfill('0') << right << setw(2) << m;
    cout << endl;
    return 0;
}