Floyed算法 O(N3) x

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 
 5 using namespace std;
 6 const int Maxn=1001;
 7 
 8 int maps[Maxn][Maxn];
 9 int ans;
10 int main() {
11     memset(maps,999999,sizeof(maps));
12     int n,m;
13     cin>>n>>m;
14     int he,ta,len;
15     for(int i=1; i<=m; i++) {
16         cin>>he>>ta>>len;
17         maps[ta][he]=maps[he][ta]=len;
18     }
19     int x,y;
20     cin>>x>>y;
21     for(int k = 1; k <= n; k++)
22         for(int i = 1; i <= n; i++)
23             for(int j = 1; j <= n; j++) {
24                 if(maps[i][j]>maps[i][k]+maps[k][j])
25                     maps[i][j]=maps[i][k]+maps[k][j];  //进行更新 
26             }
27 
28     printf("%d",maps[x][y]);
29 }