LQB20180航班时间（sscanf)

首先找找规律，两者相加除以二．

按格式读入sscanf

按格式输出printf("02d%"，m);前导0

 #include <iostream>
 #include <set>
 #include <cstring>

 using namespace std;
 //快速幂运算
 #define MAX  59084709587505
 #define LL  long long

 int Time(){
     char line[]={};
     cin.getline(line,);//getline读到换行
     int n1,m1,s1,n2,m2,s2,h=;
     if(strlen(line)==){
         sscanf(line,"%d:%d:%d %d:%d:%d",&n1,&m1,&s1,&n2,&m2,&s2);

     }
     else{
         sscanf(line,"%d:%d:%d %d:%d:%d (+%d)",&n1,&m1,&s1,&n2,&m2,&s2,&h);
     }
     int time=h**+n2*+m2*+s2-(n1*+m1*+s1);//全化成秒方便计算
     return time;

 }

 int main(){
     int T;
     (cin>>T).get();//把行尾的空格吃掉，要不会被getline 当成时间来读
     for (int i = ; i <= T; ++i) {
         int time1=Time();
         int time2=Time();
         int ans=(time2+time2)/;
         printf("%02d:%02d:%02d\n",ans/,ans/%,ans%);//秒化小时化分钟

     }

     }