Submission #432595

#	Time	Username	Problem	Language	Result	Execution time	Memory
432595		Kevin_Zhang_TW	Towns (IOI15_towns)	C++17	Compilation error	0 ms	0 KiB

towns

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb emplace_back
#define AI(i) begin(i), end(i)
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() { cerr << endl; }
template<class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ', kout(b...); }
template<class T> void debug(T l, T r) { while (l != r) cerr << *l << " \n"[next(l)==r], ++l; }
#else
#define DE(...) 0
#define debug(...) 0
#endif

const int MAX_N = 200;
#include "towns.h"

int mem_dis[MAX_N][MAX_N], n;
int dis(int a, int b) {
	if (mem_dis[a][b] || a == b) return mem_dis[a][b];
	return mem_dis[a][b] = mem_dis[b][a] = getDistance(a, b);
}

int get_far(int x) {
	int d = 0, g = -1;
	for (int i = 0;i < n;++i) if (i != x)
		if (chmax(d, dis(x, i)))
			g = i;
	return g;
}

bool too_big(int x) { return x > n / 2; }

int hubDistance(int N, int sub) {
	memset(mem_dis, 0, sizeof(mem_dis));
	n = N;

	int f = get_far(0), g = get_far(f);

	map<int, vector<int>> cnt;
	for (int i = 0;i < n;++i) {
		int y = dis(f, i), z = dis(g, i), x = dis(f, g);
		int h = (y + z - x) / 2;
		//++cnt[y - h];
		cnt[y - h].pb(i);
	}

	int ret = dis(f, g);

	for (auto [a, _] : cnt)
		chmin(ret, max(a, dis(f, g) - a));

	bool has_hub = false;

	if (sub == 4) {
		for (auto [a, child] : cnt)
			if (max(a, dis(f, g) - a) == ret) {
				if (too_big(child.size()))
					continue;
				int l = 0, r = 0;
				for (auto [w, c] : cnt) {
					if (w < a) l += c.size();
					if (w > a) r += c.size();
				}
				if (too_big(max(l, r))) continue;
				has_hub = true;
			}

	if (!has_hub) ret *= -1;
	return ret;
}

Compilation message (stderr)

towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:61:27: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
   61 |     if (too_big(child.size()))
      |                 ~~~~~~~~~~^~
towns.cpp:65:29: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
   65 |      if (w < a) l += c.size();
      |                             ^
towns.cpp:66:29: warning: conversion from 'std::vector<int>::size_type' {aka 'long unsigned int'} to 'int' may change value [-Wconversion]
   66 |      if (w > a) r += c.size();
      |                             ^
towns.cpp:74:1: error: expected '}' at end of input
   74 | }
      | ^
towns.cpp:37:33: note: to match this '{'
   37 | int hubDistance(int N, int sub) {
      |                                 ^
towns.cpp:43:24: warning: control reaches end of non-void function [-Wreturn-type]
   43 |  map<int, vector<int>> cnt;
      |                        ^~~