Submission #101470

#	Time	Username	Problem	Language	Result	Execution time	Memory
101470		shenxy	007 (CEOI14_007)	C++11	0 / 100	353 ms	16988 KiB

007

#include <cstdio>
#include <algorithm>
#include <vector>
#include <queue>
using namespace std;
const int INF = 1000000000;
int main() {
    int N, M, s, d, a, b, u, v;
    scanf("%d %d", &N, &M);
    scanf("%d %d %d %d", &s, &d, &a, &b);
    s -= 1, d -= 1, a -= 1, b -= 1;
    vector<int> adjlist[N];
    for (int i = 0; i < M; i++) {
        scanf("%d %d", &u, &v);
        adjlist[u - 1].push_back(v - 1);
        adjlist[v - 1].push_back(u - 1);
    }
    int dists[N];
    fill_n(dists, N, INF);
    dists[s] = 0;
    queue<int> q;
    q.push(s);
    while (!q.empty()) {
        int u = q.front();
        q.pop();
        for (int i = 0; i < adjlist[u].size(); i++) {
            if (dists[adjlist[u][i]] == INF) {
                dists[adjlist[u][i]] = dists[u] + 1;
                q.push(adjlist[u][i]);
            }
        }
    }
    int distd[N];
    fill_n(distd, N, INF);
    distd[d] = 0;
    q.push(d);
    while (!q.empty()) {
        int u = q.front();
        q.pop();
        for (int i = 0; i < adjlist[u].size(); i++) {
            if (distd[adjlist[u][i]] == INF) {
                distd[adjlist[u][i]] = distd[u] + 1;
                q.push(adjlist[u][i]);
            }
        }
    }
    printf("%d", min(distd[a] - dists[a], distd[b] - dists[b]) >= 0 ? min(distd[a] - dists[a], distd[b] - dists[b]): -1);
    return 0;
}

Compilation message (stderr)

007.cpp: In function 'int main()':
007.cpp:26:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < adjlist[u].size(); i++) {
                         ~~^~~~~~~~~~~~~~~~~~~
007.cpp:40:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (int i = 0; i < adjlist[u].size(); i++) {
                         ~~^~~~~~~~~~~~~~~~~~~
007.cpp:9:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &N, &M);
     ~~~~~^~~~~~~~~~~~~~~~~
007.cpp:10:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d %d %d", &s, &d, &a, &b);
     ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
007.cpp:14:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &u, &v);
         ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 30
• Subtask 2: 0 / 70