#include <iostream>
#include <cstdio>
#include <cassert>
#include <string>
#include <sstream>
#include <algorithm>
#include <set>
#include <numeric>
#include <cmath>
#include <map>
#include <vector>
#include <queue>
#include <stack>
#include <cstring>
#include <queue>
#include <numeric>
#include <iomanip>
#define ll long long
using namespace std;
map<pair<int,int>,int> mp;
const int dy[4]={0,0,1,-1};
const int dx[4]={1,-1,0,0};
vector<int> adj[4005];
const int mod = 1000000000;
int dist[4005];
int convert[4005];
void addEdge(int u,int v){
adj[u].push_back(v);
adj[v].push_back(u);
}
int bfs(int here,int n){
memset(dist,-1,sizeof(dist));
dist[here] = 0;
queue<int> q;
q.push(here);
while(!q.empty()){
int here = q.front(); q.pop();
for(int i=0;i<adj[here].size();i++){
int there = adj[here][i];
if(dist[there] == -1){
dist[there] = dist[here] + 1;
q.push(there);
}
}
}
int ret = 0;
for(int i = 0;i<4000;i++){
//if(i > here){
ret += max(dist[i],0);
ret %= mod;
//}
}
return ret;
}
int DistanceSum(int N, int *X, int *Y) {
for(int i=0;i<N;i++){
mp[make_pair(Y[i],X[i])];
}
int id = 0;
for(auto it = mp.begin();it!=mp.end();it++){
it->second = ++id;
}
for(int i=0;i<N;i++){
int x = X[i];
int y = Y[i];
for(int k=0;k<4;k++){
int ny = y + dy[k];
int nx = x + dx[k];
if(mp.find(make_pair(ny,nx)) != mp.end()){
addEdge(mp[make_pair(y,x)],mp[make_pair(ny,nx)]);
}
}
}
int tot = 0;
for(int i=1;i<=N;i++){
tot += bfs(i,N);
tot %= mod;
}
return tot;
}
Compilation message
garden.cpp: In function 'int bfs(int, int)':
garden.cpp:38:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0;i<adj[here].size();i++){
~^~~~~~~~~~~~~~~~~
/tmp/ccn6UIlA.o: In function `main':
grader.cpp:(.text.startup+0x38): undefined reference to `count_routes(int, int, int, int (*) [2], int, int*)'
collect2: error: ld returned 1 exit status
