1 #define _for(i,a,b) for(int i = (a);i < (b);i ++) 2 #define pb push_back 3 struct k 4 { 5     int a; 6     int b; 7     int diff; 8     bool operator < (k b) 9     {10         return diff
     

>& costs)17 {18 vector

v;19 _for(i,0,costs.size())20 {21 k kk;22 kk.a = costs[i][0];23 kk.b = costs[i][1];24 kk.diff = kk.a-kk.b;25 v.pb(kk);26 }27 28 sort(v.begin(),v.end());29 30 int sum = 0;31 _for(i,0,costs.size())32 sum += min(costs[i][1],costs[i][0]);33 34 _for(i,0,costs.size())35 {36 if(i < costs.size()/2 && v[i].diff>0)37 sum += v[i].diff;38 if(i >= costs.size()/2 && v[i].diff<0)39 sum += -v[i].diff;40 }41 return sum;42 }43 };