Submission #891817

#	Time	Username	Problem	Language	Result	Execution time	Memory
891817		abcvuitunggio	Towns (IOI15_towns)	C++17	61 / 100	18 ms	1116 KiB

towns

#include "towns.h"
#include <bits/stdc++.h>
using namespace std;
int n,dist[111][111],cnt[111],u,v,R,sz[2];
int d(int u, int v){
    if (u==v)
        return 0;
    if (u>v)
        swap(u,v);
    if (dist[u][v])
        return dist[u][v];
    return dist[u][v]=getDistance(u,v);
}
int calc(vector <int> ve, int h=0){
    if (h==3)
        return R;
    vector <int> l,r;
    int j=ve.back();
    l.push_back(j);
    ve.pop_back();
    for (int i:ve){
        int c=1;
        int x=(d(i,u)+d(i,v)-d(u,v))/2,y=(d(j,u)+d(j,v)-d(u,v))/2;
        if (d(i,j)<x+y){
            l.push_back(i);
            if (l.size()>n/2)
                return -R;
        }
        else
            r.push_back(i);
    }
    if (r.size()<=n/2)
        return R;
    return calc(r,h+1);
}
int hubDistance(int N, int sub){
    n=N;
    memset(dist,0,sizeof(dist));
    pair <int, int> mx={0,-1};
    for (int i=0;i<N;i++)
        mx=max(mx,{d(0,i),i});
    u=mx.second;
    mx={0,-1};
    for (int i=0;i<N;i++)
        mx=max(mx,{d(u,i),i});
    v=mx.second,R=1e9,sz[0]=sz[1]=0;
	for (int i=0;i<N;i++)
        R=min(R,abs(d(i,u)-d(i,v)));
    vector <int> a,b,tmp;
    for (int i=0;i<N;i++){
        int val=d(i,u)-d(i,v);
        if (val<-R)
            sz[0]++;
        if (val==-R)
            a.push_back(i);
        if (val==R)
            b.push_back(i);
        if (val>R)
            sz[1]++;
    }
    if (!R)
        b.clear();
    R=(R+d(u,v))/2;
    if (sub<3)
        return R;
    if (max(sz[0],sz[1])>N/2)
        return -R;
    if (min(sz[1]+b.size(),sz[0]+a.size())>N/2)
        return -R;
    if (max(a.size(),sz[1]+b.size())<=N/2)
        return R;
    if (max(b.size(),sz[0]+a.size())<=N/2)
        return R;
    return calc(b.size()+sz[1]<=N/2?a:b);
}

Compilation message (stderr)

towns.cpp: In function 'int d(int, int)':
towns.cpp:5:18: warning: declaration of 'v' shadows a global declaration [-Wshadow]
    5 | int d(int u, int v){
      |              ~~~~^
towns.cpp:4:33: note: shadowed declaration is here
    4 | int n,dist[111][111],cnt[111],u,v,R,sz[2];
      |                                 ^
towns.cpp:5:11: warning: declaration of 'u' shadows a global declaration [-Wshadow]
    5 | int d(int u, int v){
      |       ~~~~^
towns.cpp:4:31: note: shadowed declaration is here
    4 | int n,dist[111][111],cnt[111],u,v,R,sz[2];
      |                               ^
towns.cpp: In function 'int calc(std::vector<int>, int)':
towns.cpp:26:25: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   26 |             if (l.size()>n/2)
      |                 ~~~~~~~~^~~~
towns.cpp:22:13: warning: unused variable 'c' [-Wunused-variable]
   22 |         int c=1;
      |             ^
towns.cpp:32:17: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   32 |     if (r.size()<=n/2)
      |         ~~~~~~~~^~~~~
towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:68:43: warning: comparison of integer expressions of different signedness: 'const long unsigned int' and 'int' [-Wsign-compare]
   68 |     if (min(sz[1]+b.size(),sz[0]+a.size())>N/2)
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~
towns.cpp:70:37: warning: comparison of integer expressions of different signedness: 'const long unsigned int' and 'int' [-Wsign-compare]
   70 |     if (max(a.size(),sz[1]+b.size())<=N/2)
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
towns.cpp:72:37: warning: comparison of integer expressions of different signedness: 'const long unsigned int' and 'int' [-Wsign-compare]
   72 |     if (max(b.size(),sz[0]+a.size())<=N/2)
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~
towns.cpp:74:31: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   74 |     return calc(b.size()+sz[1]<=N/2?a:b);
      |                 ~~~~~~~~~~~~~~^~~~~

• Subtask 1: 13 / 13
• Subtask 2: 12 / 12
• Subtask 3: 13 / 13
• Subtask 4: 10 / 10
• Subtask 5: 13 / 13
• Subtask 6: 0 / 39