Submission #810640

#	Time	Username	Problem	Language	Result	Execution time	Memory
810640		AkramElOmrani	Ideal city (IOI12_city)	C++17	100 / 100	103 ms	17116 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__);

#define ll long long
const int mod = 1e9;
int add(int a, int b) {
  a += b;
  if(a > mod) {
	a -= mod;
  }
  return a;
}
int mul(int a, int b) {
	a = (ll)a * b % mod;
	return a;
}
int sub(int a, int b) {
	a -= b;
	if(a < 0) {
		a += mod;
	}
	return a;
}
vector<pair<int, int>> dir = {{-1, 0}, {1, 0}, {0, 1}, {0, -1}};
vector<vector<int>> adj;
vector<int> sz;
vector<bool> vis;
int n;

int tot = 0;
int get_sz(int node)  {
	vis[node] = 1;
	for(int x : adj[node]) {
		if(vis[x]) continue;
		sz[node] = add(sz[node], get_sz(x));
	}
	return sz[node];
}
void dfs(int node) {
	vis[node] = 1;
	for(int x : adj[node]) {
		if(vis[x]) continue;
		// dbg(x, sz[x]);
		tot = add(tot, mul(sz[x], (n - sz[x])));
		dfs(x);
	}
}

int cal(int* X, int* Y) {
	tot = 0;
	map<int, vector<int>> mp;
	adj.clear();
	adj.resize(n);
	sz.clear();
	sz.resize(n);
	vis.clear();
	vis.resize(n);
	map<pair<int, int>, int> cc;
	for(int i = 0; i < n; ++i) {
		mp[X[i]].push_back(Y[i]);
	}
	int nbr = 0;
	for(auto[id, v] : mp) {
		sort(v.begin(), v.end());
		int c = 1;
		cc[{id, v[0]}] = nbr;
		for(int i = 1; i < v.size(); ++i) {
			if(v[i - 1] + 1 == v[i]) { // you can expend the edge of the tree
				c++;
			} else {
				sz[nbr++] = c;
				c = 1;
			}
			cc[{id, v[i]}] = nbr; // edges having the same cc
		}
		sz[nbr++] = c; c = 0;
		for(int i = 0; i < v.size(); ++i) {
			auto it = cc.find({id - 1, v[i]}); // link those having adjacent y
			if(it == cc.end()) continue;
			int ff = it->second;
			int ss = cc[{id, v[i]}];
			adj[ff].push_back(ss);
			adj[ss].push_back(ff);
		}
	}
	get_sz(0);
	vis.assign(n, 0);
	dfs(0);
	return tot;
}

int DistanceSum(int n_, int *X, int *Y) {
	n = n_;
	int cal_x = cal(X, Y);
	int cal_y = cal(Y, X);
	int ans = add(cal_x, cal_y);
	return ans;
}

// int main() {

//   /* Set input and output buffering */
//   // char *inbuf, *outbuf;
//   // inbuf = (char*) malloc(inbuf_len * sizeof(char));
//   // outbuf = (char*) malloc(outbuf_len * sizeof(char));
//   // tmp = setvbuf(stdin, inbuf, _IOFBF, inbuf_len);
//   // assert(tmp == 0);
//   // tmp = setvbuf(stdout, outbuf, _IOFBF, outbuf_len);
//   // assert(tmp == 0);

//   int N, i;
//   cin >> N;
//   int *sq_x, *sq_y;
//   sq_x = (int*) malloc(N * sizeof(int));
//   sq_y = (int*) malloc(N * sizeof(int));
//   for (i = 0; i < N; i++) {
//     cin >> sq_x[i] >> sq_y[i];
//   }
//   int ds = DistanceSum(N, sq_x, sq_y);
//   cout << ds;

//   return 0;

// }

Compilation message (stderr)

city.cpp: In function 'int cal(int*, int*)':
city.cpp:74:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |   for(int i = 1; i < v.size(); ++i) {
      |                  ~~^~~~~~~~~~
city.cpp:84:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   84 |   for(int i = 0; i < v.size(); ++i) {
      |                  ~~^~~~~~~~~~

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