Submission #810496

#	Time	Username	Problem	Language	Result	Execution time	Memory
810496		AkramElOmrani	Ideal city (IOI12_city)	C++17	11 / 100	1075 ms	1876 KiB

city

#include <bits/stdc++.h>
using namespace std;

template<typename A, typename B> ostream& operator<<(ostream &os, const pair<A, B> &p) { return os << '(' << p.first << ", " << p.second << ')'; }
template<typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type> ostream& operator<<(ostream &os, const T_container &v) { os << '{'; string sep; for (const T &x : v) os << sep << x, sep = ", "; return os << '}'; }
 
void dbg_out() { cerr << endl; }
template<typename Head, typename... Tail> void dbg_out(Head H, Tail... T) { cerr << ' ' << H; dbg_out(T...); }
#define dbg(...) cerr << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__);

const int mod = 1e9;
void add(int& a, int b) {
  a += b;
  if(a > mod) {
	a -= mod;
  }
}
vector<pair<int, int>> dir = {{-1, 0}, {1, 0}, {0, 1}, {0, -1}};

int DistanceSum(int n, int *X, int *Y) {
	int sum = 0;
	map<pair<int, int>, int> mp;
	for(int i = 0; i < n; ++i) {
		mp[{X[i], Y[i]}] = i;
	}
	const int INF = 1e9 + 5;
	int ans = 0;
	for(int i = 0; i < n; ++i) {
	// start a bfs
	vector<int> dist(n, INF);
	queue<int> q;
	q.push(i);
	dist[i] = 0;
	while(!q.empty()) {
	  int sz = q.size();
	  for(int i = 0; i < sz; ++i) {
		int p = q.front(); q.pop();
		for(auto[row, col] : dir) {
		  row += X[p];
		  col += Y[p];
		  auto it = mp.find({row, col});
		  if(it == mp.end()) continue;
		  if(dist[it->second] != INF) continue;
		  dist[it->second] = dist[p] + 1;
		  q.push(it->second);
		}
	  }
	}
	// dbg(dist)
	for(int j = i + 1; j < n; ++j) {
	  add(ans, dist[j]);
	  // dbg(ans, dist[j])
	}
  }
  return ans;
}

Compilation message (stderr)

city.cpp: In function 'int DistanceSum(int, int*, int*)':
city.cpp:22:6: warning: unused variable 'sum' [-Wunused-variable]
   22 |  int sum = 0;
      |      ^~~

• Subtask 1: 11 / 11
• Subtask 2: 0 / 21
• Subtask 3: 0 / 23
• Subtask 4: 0 / 45