C - Heavy Transportation

Posted 2020-11-03 jaydenouyang

 1 //改版dijkstra
 2 #include <iostream>
 3 #include <algorithm>
 4 
 5 #define Faster ios::sync_with_stdio(false),cin.tie(0)
 6 #define Read freopen("in.txt","r",stdin),freopen("out.txt","w",stdout)
 7 #define Close fclose(stdin),fclose(stdout)
 8 const int maxn = 1000+5;
 9 using namespace std;
10 
11 const int INF = 0xfffff;
12 
13 int mp[maxn][maxn];
14 bool v[maxn];
15 int n, m;
16 int dis[maxn];
17 
18 void dij(int be){
19     int Min, p;
20     v[be] = false;
21     for(int i = 1;i <= n;i++){
22         dis[i] = mp[i][be];
23     }
24     dis[be] = 0;
25 
26     for(int i = 1;i <= n;i++){
27         Min = 0;
28         for(int j = 1;j <= n;j++){
29             if(v[j] && Min < dis[j]){
30                 p = j;
31                 Min = dis[j];
32             }
33         }
34         if(Min == 0)
35             break;
36         v[p] = false;
37         for(int j = 1;j <= n;j++){
38             dis[j] = max(dis[j], min(dis[p],mp[p][j]));
39         }
40     }
41 }
42 
43 int main(){
44     Faster;
45     int t;
46     int cnt = 0;
47     cin >> t;
48     while(t--){
49         cnt++;
50         cin >> n >> m;
51         for(int i = 0;i <= n;i++){
52             dis[i] = 0;
53             v[i] = true;
54             for(int j = 0;j <= n;j++){
55                 mp[i][j] = 0;
56             }
57         }
58         for(int i = 0;i < m;i++){
59             int x, y, z;
60             cin >> x >> y >> z;
61             if(mp[x][y] < z){
62                 mp[x][y] = mp[y][x] = z;
63             }
64         }
65 
66         dij(1);
67         cout << "Scenario #" << cnt << ":"<< endl;
68         cout << dis[n] << endl << endl;
69     }
70     return 0;
71 }