제출 #400279

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
400279		ly20	도시들 (IOI15_towns)	C++17	39 / 100	21 ms	400 KiB

towns

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


const int MAXN = 120;
/*
int ds[MAXN][MAXN];
int getDistance(int a, int b) {
    return ds[a][b];
}
*/
int dist[MAXN][MAXN];
int gd(int a, int b) {
    if(dist[a][b] == 0) {
        dist[a][b] = getDistance(a, b);
        dist[b][a] = dist[a][b];
    }
    return dist[a][b];
}
int pai[MAXN], sz[MAXN];
int find(int v) {
    if(v == pai[v]) return v;
    return pai[v] = find(pai[v]);
}
void une(int a, int b) {
    a = find(a); b = find(b);
    if(a == b) return;
    if(sz[a] > sz[b]) swap(a, b);
    pai[a] = b;
    sz[b] += sz[a];
}
int hubDistance(int n, int sub) {
	//int resp = 0;
	for(int i = 0; i < MAXN; i++) {
        for(int j = 0; j < MAXN; j++) {
            dist[i][j] = 0;
        }
	}
	int mx1 = 1, mx = 0;
	int a, b;
	for(int i = 1; i < n; i++) {
        int d = gd(1, i);
        if(d > mx) {
            mx = d; mx1 = i;
        }
	}
    a = mx1; mx = 0;
    for(int i = 0; i < n; i++) {
        if(i == a) continue;
        int d = gd(a, i);
        if(d > mx) {
            mx = d; mx1 = i;
        }
    }
    b = mx1;
    int dim = mx;
    //set <int> di;
    int resp = dim;
    vector <int> ns;
    for(int i = 0; i < n; i++) {
            pai[i] = i; sz[i] = 1;
        if(i == a || i == b) continue;
        int d = gd(a, i) - (gd(a, i) + gd(b, i) - dim) / 2;
        resp = min(resp, max(d, dim - d));
        ns.push_back(d);
    }
    resp = resp * -1;
    int esq1 = -1, esq2 = -1;
    for(int i = 0; i < n; i++) {
        int d = gd(a, i) - (gd(a, i) + gd(b, i) - dim)/ 2;
        //printf("%d %d %d\n", i, d, dim - d);
        if(max(d, dim - d) != -resp) continue;
        //printf("oi\n");
        if(d == esq1 || d == esq2) continue;
        //printf("%d\n", i);
        if(esq1 == -1) esq1 = d;
        else esq2 = d;
        vector <int> cur;
        int ce = 0, cd = 0;
        for(int j = 0; j < n; j++) {
            int dt = gd(a, j) - (gd(a, j) + gd(b, j) - dim) / 2;
            if(dt < d) {
                ce++;
            }
            else if(dt > d) {
                cd++;
            }
            else cur.push_back(j);
        }
        if(ce > n / 2 || cd > n / 2) continue;
        //return -resp;
        if(cur.size() <= n / 2) return -resp;
        //else continue;
        //printf("%d\n", cur.size());
        stack <int> pilha;
        for(int j = 0; j < cur.size(); j++) {
            int id = cur[j];
            if(pilha.empty()) {
                pilha.push(id);
            }
            else {
                int k = pilha.top(), l = cur[j];
                int d1 = gd(a, k) + gd(b, k) - gd(a, b), d2 = gd(a, l) + gd(b, l) - gd(a, b), db = gd(k, l);
                if(d1 + d2 != 2 * db) {
                    une(l, pilha.top());
                    pilha.push(l);
                }
                else pilha.pop();
            }
        }
        if(pilha.empty()) return -resp;
        int bs = pilha.top();
        int qt = 1;
        for(int j = 0; j < cur.size(); j++) {
            int id = cur[j];
            if(id == bs) continue;
            int k = find(bs), l = find(id);
            int d1 = gd(a, k) + gd(b, k) - gd(a, b), d2 = gd(a, l) + gd(b, l) - gd(a, b), db = gd(k, l);
            if(d1 + d2 != 2 * db) qt++;
        }
        if(qt <= n / 2) return -resp;
    }
	return resp;
}
/*
int main() {
    int n;
    scanf("%d", &n);
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            scanf("%d", &ds[i][j]);
        }
    }
    printf("%d\n", hubDistance(n, 0));
    return 0;
}

*/

컴파일 시 표준 에러 (stderr) 메시지

towns.cpp: In function 'int hubDistance(int, int)':
towns.cpp:93:23: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   93 |         if(cur.size() <= n / 2) return -resp;
      |            ~~~~~~~~~~~^~~~~~~~
towns.cpp:97:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   97 |         for(int j = 0; j < cur.size(); j++) {
      |                        ~~^~~~~~~~~~~~
towns.cpp:115:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  115 |         for(int j = 0; j < cur.size(); j++) {
      |                        ~~^~~~~~~~~~~~
towns.cpp:33:28: warning: unused parameter 'sub' [-Wunused-parameter]
   33 | int hubDistance(int n, int sub) {
      |                        ~~~~^~~

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• Subtask 3: 13 / 13
• Subtask 4: 0 / 10
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• Subtask 6: 0 / 39