#include<bits/stdc++.h>
using namespace std;
#define vi vector<int>
#define vvi vector<vi>
#define vs vector<string>
#define pb push_back
#define P pair<int,int>
#define vp vector<P>
#define PP pair<int,P>
#define vpp vector<PP>
#define fi first
#define se second
#define INF 1e9
#define MOD 1000000007
#define REP(i,n) for(int i=0;i<n;i++)
#define REPR(i,n) for(int i=n;i>=0;i--)
#define FOR(i,m,n) for(int i=m;i<n;i++)
#define all(x) (x).begin(),(x).end()
int mi(double t){
    double p=t-(int)t;
    double q=p*60.0;
    return (int)q;
}
int main(){
    int a,b;
    cin>>a>>b;
    string st;
    cin>>st;
    a-=9;
    double t=stod(st.substr(3,st.size()-3));
    a+=(int)t;
    b+=mi(t);
    printf("%02d:%02d\n",(a+24)%24,b);
    return 0;
}