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| #pragma GCC optimize(2) #pragma GCC optimize(3, "Ofast", "inline") #include<bits/stdc++.h> using namespace std;
typedef long long ll; typedef __int128 int128;
namespace FastIO { char buf[1 << 20], *p1, *p2; #define getchar() (p1 == p2 && (p2 = (p1 = buf) + fread(buf, 1, 1 << 20, stdin), p1 == p2) ? EOF : *p1++) template<typename T> inline T read(T& x) { x = 0; int f = 1; char ch; while (!isdigit(ch = getchar())) if (ch == '-') f = -1; while (isdigit(ch)) x = (x << 1) + (x << 3) + (ch ^ 48), ch = getchar(); x *= f; return x; } template<typename T, typename... Args> inline void read(T& x, Args &...x_) { read(x); read(x_...); return; } inline ll read() { ll x; read(x); return x; } inline void read(char *s) { scanf("%s", s + 1); } }; using namespace FastIO;
const int N = 2e5 + 10;
struct Edge { int to, nt, wt; Edge() {} Edge(int to, int nt, int wt) : to(to), nt(nt), wt(wt) {} }e[N << 1]; int hd[N], cnte; inline void AddEdge(int u, int v, int w) { e[++cnte] = Edge(v, hd[u], w); hd[u] = cnte; }
int n;
inline void Input() { read(n); int u, v, w; for(int i = 1; i < n; i++) { read(u, v, w); AddEdge(u, v, w); AddEdge(v, u, w); } }
int fa[N], dep[N]; ll dis[N]; int ans;
int vis[N]; ll ma[N];
inline void Dfs1(int u, int f) { dep[u] = dep[f] + 1; fa[u] = f; for(int i = hd[u]; i ; i = e[i].nt) { int v = e[i].to; if(v == f) continue; dis[v] = dis[u] + e[i].wt; Dfs1(v, u); } }
inline void Dfs2(int u) { ll mx = -1; int js = 0, js2 = 0; for(int i = hd[u]; i ; i = e[i].nt) { int v = e[i].to; if(v == fa[u])continue; Dfs2(v); if(ma[v] >= mx) { if(ma[v] > mx) { mx = ma[v]; js = 1; } else js++; } if(ma[v] - dis[u] == dis[u]) { js2++; } } if(vis[u]) { if(js2) { ans -= dep[u] - 1; printf("%d\n", max(ans, 0)); return exit(0); } else if(js > 1) { ans = dep[u] - 1; } } mx = max(mx, dis[u]); ma[u]=mx; }
inline void Work() { Dfs1(1, 0); memset(fa, 0, sizeof(fa)); int du = 0, dv = 0; for(int i = 1; i <= n; i++) { if(dis[i] > dis[du]) { du = i; } } memset(dis, 0, sizeof(dis)); Dfs1(du, 0); for(int i = 1; i <= n; i++) { if(dis[i] > dis[dv]) { dv=i; } } printf("%lld\n", dis[dv]); ans = dep[dv]-1; int now = dv; while(now!=du) { vis[now] = 1; now = fa[now]; } Dfs2(du); printf("%d\n",ans); }
int main() { int T = 1; while(T--) { Input(); Work(); } return 0; }
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