59 lines
1.2 KiB
C++
59 lines
1.2 KiB
C++
#include <bits/stdc++.h>
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using namespace std;
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const int N = 1010; //图的最大点数量
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int n, m;
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/**
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共提供两组数据，样例1为不连通用例，样例2为连通用例
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样例1：不连通，5号结点为独立的
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5 4
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1 2
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2 3
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3 4
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1 4
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样例2：连通，不存在独立结点
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5 4
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1 2
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2 3
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3 4
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1 5
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检测各种算法是否能准确获取结果
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*/
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//用floyd来判断起点是否可以达到终点
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int dis[N][N]; //邻接矩阵
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void floyd() {
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for (int k = 1; k <= n; k++)
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for (int i = 1; i <= n; i++)
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for (int j = 1; j <= n; j++)
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dis[i][j] = dis[i][j] || (dis[i][k] && dis[k][j]);
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}
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int main() {
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//采用邻接矩阵建图
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cin >> n >> m;
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//m条边
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for (int i = 1; i <= m; i++) {
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int u, v;
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cin >> u >> v;
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//双向建边
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dis[u][v] = 1;
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dis[v][u] = 1;
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}
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//调用floyd
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floyd();
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for (int i = 1; i <= n; i++)
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for (int j = 1; j <= n; j++)
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if (!dis[i][j]) {
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printf("图不是连通的\n");
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cout << i << " " << j << endl;
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exit(0);
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}
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printf("图是连通的\n");
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return 0;
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} |