求两次单源最短路,注意无向图可能有重边,所以需要去重 #define IO std::ios::sync_with_stdio(0),cin.tie(0),cout.tie(0) #define bug(x) cout<<#x<<" is "<<x<<endl #include<bits/stdc++.h> typedef long long ll; using namespace std; const int N = 1e5 + 5; vector<int>g[N]; int n, m, k; str...