int main(){
ll answer = 0;
int n;
scanf("%d", &n);
ll tutorsx [n]; memset(tutorsx , 0, sizeof(tutorsx ));
ll tutorsy [n]; memset(tutorsy , 0, sizeof(tutorsy ));
ll studentsx[n]; memset(studentsx, 0, sizeof(studentsx));
ll studentsy[n]; memset(studentsy, 0, sizeof(studentsy));
for(int i=0; i<n; i++)
scanf("%lld %lld", &studentsx[i], &studentsy[i]);
for(int i=0; i<n; i++)
scanf("%lld %lld", &tutorsx[i], &tutorsy[i]);
ll distances[n][n];
for(int i=0; i<n; i++)
for(int j=0; j<n; j++)
distances[i][j] = abs(tutorsx[i] - studentsx[j]) +
abs(tutorsy[i] - studentsy[j]);
ll low = 0, high = 10000000000, mid;
while(high - low > 2){
init(n, n);
mid = (low + high) / 2;
for(int i = 0; i < n; i++)
for(int j = 0; j < n; j++)
if(distances[i][j] <= mid)
addEdge(i, j);
if(maxMatching() == n)
high = mid + 1;
else if(maxMatching() < n)
low = mid + 1;
}
init(n, n);
for(int i = 0; i < n; i++)
for(int j = 0; j < n; j++)
if(distances[i][j] <= low)
addEdge(i, j);
if(maxMatching() == n)
answer = low;
else
answer = low + 1;
printf("%lld\n", answer);
return 0;
}
// assign rooms to events in timeslot t
void Solution::assignRooms(int t)
{
val.clear();
dad.clear();
vector<int> assigned; // vector keeping track for each event if it is assigned or not
int lessBusy= 0; // room occupied by the fewest events
int busy[data->n_of_rooms]; // number of events in a room
int N = (int)timeslot_events[t].size();
int V = N+2+data->n_of_rooms;
// initialize the bipartite graph
size = IntMatrixAlloc(V+1,V+1);
flow = IntMatrixAlloc(V+1,V+1);
for (int i = 0; i <= V; i++) {
for (int j = 0; j <= V; j++) {
size[i][j] = 0;
flow[i][j] = 0;
}
}
for(int i =0; i < N; i++){
size[1][i+2] = 1;
size[i+2][1] = -1;
for(int j = 0; j < data->n_of_rooms; j++)
if(data->possibleRooms[timeslot_events[t][i]][j] == 1){
size[i+2][N+j+2] = 1;
size[N+j+2][i+2] = -1;
size[N+j+2][V] = 1;
size[V][N+j+2] = -1;
}
}
maxMatching(V); // apply the matching algorithm
for(int i =0; i < N; i++){ // check if there are unplaced events
assigned.push_back(0);
for(int j = 0; j < data->n_of_rooms; j++){
if(flow[i+2][N+j+2] == 1){
sln[timeslot_events[t][i]].second = j;
// cout << "room " << j << endl;
assigned[i] = 1;
//busy[j] =+ 1;
busy[j] += 1;
}
}
}
for(int i = 0; i < N; i++){ // place the unplaced events in the less busy possible rooms
if(assigned[i] == 0){
for(int j = 0; j < data->n_of_rooms; j++){
if(data->possibleRooms[timeslot_events[t][i]][j] == 1){
lessBusy = j;
break;
}
}
for(int j = 0; j < data->n_of_rooms; j++){
if(data->possibleRooms[timeslot_events[t][i]][j] == 1){
if(busy[j] < busy[lessBusy])
lessBusy = j;
}
}
sln[timeslot_events[t][i]].second = lessBusy;
}
}
free(size); // don't forget to free the memory
free(flow);
}
