#include<vector>
#include<iostream>
#include<string>
#include<algorithm>
#include<math.h>
#include<map>
#include<functional>
#include<queue>
#include<stack>
#include<string.h>
#include<list>
#define MOD 10000
#define INF 1000000000
#define MAX 101
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
int main() {
    int a,b;
    cin>>a>>b;
    string s;
    cin>>s;
    int zt=0;
    int zm=0;
    if(s.length()>6){
        if(s[5]=='.'){
            zt+=(s[4]-'0');
            zm+=(s[6]-'0')*6;
        }else{
            zt+=(s[4]-'0')*10+(s[5]-'0');
            zm+=(s[7]-'0')*6;
        }
    }else if(s.length()>5){
        zt+=(s[4]-'0')*10+(s[5]-'0');
    }else{
        zt+=(s[4]-'0');
    }
        
    if(s[3]=='+'){
        a+=zt-9;
        b+=zm;
    }else{
        a-=9+zt;
        b-=zm;
    }
    if(b>=60){
        while(1){
            b-=60;
            a+=1;
            if(b<60){
                break;
            }
        }
    }
    if(b<0){
        while(1){
            b+=60;
            a-=1;
            if(b>=0){
                break;
            }
        }
    }
    if(a>23){
        a-=24;
    }
    if(a<0){
        a+=24;
    }
    if(a<10){
        cout<<0;
    }
    cout<<a<<":";
    if(b<10){
        cout<<0;
    }
    cout<<b<<endl;

}