Submission #586470

#	Time	Username	Problem	Language	Result	Execution time	Memory
586470		krit3379	City Mapping (NOI18_citymapping)	C++17	32 / 100	60 ms	24660 KiB

citymapping

#include<bits/stdc++.h>
#include "citymapping.h"
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define N 1005

struct A{
    int a,b,w;
};

long long dis[N][N],dis1[N],ma,id,last,last_node;
vector<pair<long long,long long>> v,g[N];
vector<A> edge;
bitset<N> vis;

void dfs(int s,int f){
    vis[s]=true;
    for(auto [x,w]:g[s]){
        if(vis[x])continue;
        if(!f||dis[f][s]+dis[s][x]==dis[f][x])dfs(x,s),edge.push_back({s,x,w});
    }
}

void find_roads(int n,int q,int a[], int b[],int w[]){
    int i,j;
    if(q==500000){
        for(i=1;i<=n;i++)for(j=i+1;j<=n;j++){
            long long x=get_distance(i,j);
            dis[i][j]=dis[j][i]=x;
            g[i].push_back({j,x});
            g[j].push_back({i,x});
        }
        dfs(1,0);
        for(i=0;i<edge.size();i++){
            a[i]=edge[i].a;
            b[i]=edge[i].b;
            w[i]=edge[i].w;
        }
    }
    else if(q==12000){
        for(i=2;i<=n;i++)dis1[i]=get_distance(1,i);
        for(i=1;i<=n;i++)if(dis1[i]>ma)ma=dis1[i],id=i;
        for(i=1;i<=n;i++)if(i!=id)v.push_back({get_distance(id,i),i});
        sort(v.begin(),v.end());
        last=0;
        last_node=id;
        for(i=0;i<v.size();i++){
            a[i]=last_node;
            b[i]=v[i].second;
            w[i]=v[i].first-last;
            last=v[i].first;
            last_node=v[i].second;
        }
    }
}

Compilation message (stderr)

citymapping.cpp: In function 'void dfs(int, int)':
citymapping.cpp:21:74: warning: narrowing conversion of 'x' from 'std::tuple_element<0, std::pair<long long int, long long int> >::type' {aka 'long long int'} to 'int' [-Wnarrowing]
   21 |         if(!f||dis[f][s]+dis[s][x]==dis[f][x])dfs(x,s),edge.push_back({s,x,w});
      |                                                                          ^
citymapping.cpp:21:76: warning: narrowing conversion of 'w' from 'std::tuple_element<1, std::pair<long long int, long long int> >::type' {aka 'long long int'} to 'int' [-Wnarrowing]
   21 |         if(!f||dis[f][s]+dis[s][x]==dis[f][x])dfs(x,s),edge.push_back({s,x,w});
      |                                                                            ^
citymapping.cpp: In function 'void find_roads(int, int, int*, int*, int*)':
citymapping.cpp:35:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<A>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   35 |         for(i=0;i<edge.size();i++){
      |                 ~^~~~~~~~~~~~
citymapping.cpp:48:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |         for(i=0;i<v.size();i++){
      |                 ~^~~~~~~~~

• Subtask 1: 0 / 9
• Subtask 2: 0 / 16
• Subtask 3: 13 / 13
• Subtask 4: 19 / 19
• Subtask 5: 0 / 43