1133 A. Middle of the Contest.cpp

//Bismillahir Rahmanir Rahim
#include<bits/stdc++.h>
#define ll              long long
#define ull             unsigned long long
#define pb              push_back
#define fastread()      (ios_base:: sync_with_stdio(false),cin.tie(NULL));
using namespace std;
int main()
{
    fastread();
    int h1,h2,h3,h4,h5,m1,m2,m3;
    char c;
    cin>>h1>>c>>m1;
    cin>>h2>>c>>m2;
    h3 = h1 * 60 + m1;
    h4 = h2 * 60 + m2;
    h5 = (h3 + h4)/2;
    int h = h5/60;
    int m = h5 % 60;
    if(h > 9 && m > 9){
        cout<<h<<":"<<m<<endl;
    }
    else{
        if(h < 10){
            cout<<0;
        }
        cout<<h<<":";
        if(m < 10){
            cout<<0;
        }
        cout<<m<<endl;
    }
    return 0;
}