LCA
A - How far away ? HDU - 2586 LCA倍增 #include<cstdio> #include<iostream> #include<algorithm> #include<cstring> #include<cmath> #include<stack> #include<cstdlib> #include<queue> #include<set> #include<string.h> #include<vector> #include<deque> #include<map> using namespace std; #define INF 0x3f3f3f3f3f3f3f3f #define inf 0x3f3f3f3f #define eps 1e-4 #define bug printf("*********\n") #define debug(x) cout<<#x"=["<<x<<"]" <<endl typedef long long LL; typedef long long ll; const int maxn = 4e4 + 5; const int mod = 998244353; int cnt,DEG = 30; int vis[maxn],head[maxn],dep[maxn],fa[maxn][30],dis[maxn];