1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146
|
#include <bits/stdc++.h> using namespace std; #define int long long #define resetIO(x) \ freopen(#x ".in", "r", stdin), freopen(#x ".out", "w", stdout) #define debug(fmt, ...) \ fprintf(stderr, "[%s:%d] " fmt "\n", __FILE__, __LINE__, ##__VA_ARGS__) template <class _Tp> inline _Tp& read(_Tp &x) { bool sign = false; char ch = getchar(); long double tmp = 1; for (; !isdigit(ch); ch = getchar()) sign |= (ch == '-'); for (x = 0; isdigit(ch); ch = getchar()) x = x * 10 + (ch ^ 48); if (ch == '.') for (ch = getchar(); isdigit(ch); ch = getchar()) tmp /= 10.0, x += tmp * (ch ^ 48); return sign ? (x = -x) : x; } template <class _Tp> inline void write(_Tp x) { if (x < 0) putchar('-'), x = -x; if (x > 9) write(x / 10); putchar((x % 10) ^ 48); } const int MAXN = 3e5 + 10; const int MAXM = 5e5 + 10; const int MAXK = 20; const int INFL = 0x3f3f3f3f3f3f3f3f; struct graph { struct edge { int u, v, w; } e[MAXM]; int head[MAXN], nxt[MAXM], tot; void addedge(int u, int v, int w) { e[++tot] = {u, v, w}; nxt[tot] = head[u]; head[u] = tot; } }; int n, m, k, inde, h[MAXN], dfn[MAXN], dep[MAXN]; int fa[MAXN][MAXK], mn[MAXN][MAXK], dp[MAXN], sta[MAXN], top; bool tag[MAXN]; graph tr, vtr; void build_tr(int u, int f, int w) { dfn[u] = ++inde, dep[u] = dep[f] + 1; fa[u][0] = f, mn[u][0] = w; for (int i = 1; i < MAXK; ++i) fa[u][i] = fa[fa[u][i - 1]][i - 1]; for (int i = 1; i < MAXK; ++i) mn[u][i] = min(mn[u][i - 1], mn[fa[u][i - 1]][i - 1]); for (int i = tr.head[u]; i; i = tr.nxt[i]) if (tr.e[i].v != f) build_tr(tr.e[i].v, u, tr.e[i].w); } int lca(int u, int v) { if (dep[u] < dep[v]) swap(u, v); int t = dep[u] - dep[v]; for (int i = MAXK - 1; ~i; --i) if ((t >> i) & 1) u = fa[u][i]; if (u == v) return u; for (int i = MAXK - 1; ~i; --i) if (fa[u][i] != fa[v][i]) u = fa[u][i], v = fa[v][i]; return fa[u][0]; } int minpath(int f, int u) { int t = dep[f] - dep[u]; int ret = INFL; for (int i = MAXK - 1; ~i; --i) if ((t >> i) & 1) ret = min(ret, mn[u][i]), u = fa[u][i]; return ret; } void add_vedge(int u, int v) { vtr.addedge(u, v, minpath(u, v)); } void build_vtr() { sort(h + 1, h + k + 1, [](int x, int y) { return dfn[x] < dfn[y]; }); sta[top = 1] = 1, vtr.tot = 0, vtr.head[1] = 0; for (int i = 1; i <= k; ++i) { if (h[i] == 1) continue; int l = lca(sta[top], h[i]); if (l != sta[top]) { while (dfn[sta[top - 1]] > dfn[l]) add_vedge(sta[top - 1], sta[top]), --top; if (sta[top - 1] == l) add_vedge(l, sta[top]), --top; else vtr.head[l] = -1, add_vedge(l, sta[top]), sta[top] = l; } vtr.head[h[i]] = 0, sta[++top] = h[i]; } for (int i = 1; i < top; ++i) add_vedge(sta[i], sta[i + 1]); } void dfs(int u) { dp[u] = 0; for (int i = vtr.head[u]; i; i = vtr.nxt[i]) { int v = vtr.e[i].v, w = vtr.e[i].w; dfs(v); if (tag[v]) dp[u] += w; else dp[u] += min(dp[v], w); } } signed main() { read(n); for (int i = 1; i < n; ++i) { int u, v, w; read(u), read(v), read(w); tr.addedge(u, v, w); tr.addedge(v, u, w); } fill(mn[0], mn[0] + MAXK, INFL); build_tr(1, 0, INFL); read(m); while (m--) { read(k); for (int i = 1; i <= k; ++i) read(h[i]), tag[h[i]] = true; build_vtr(); dfs(1); write(dp[1]), putchar('\n'); for (int i = 1; i <= k; ++i) tag[h[i]] = false; } return 0; }
|