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ID题目提交者结果用时内存语言文件大小提交时间测评时间
#692995#5439. Meet in the MiddleningagoTL 0ms0kbC++148.2kb2024-10-31 15:20:402024-10-31 15:20:41

Judging History

你现在查看的是最新测评结果

  • [2024-10-31 15:20:41]
  • 评测
  • 测评结果:TL
  • 用时:0ms
  • 内存:0kb
  • [2024-10-31 15:20:40]
  • 提交

answer

#include <cstdio>
#include <cstring>
#include <algorithm>
#include <numeric>
#include <vector>
#include <queue>
#include <map>
#include <cmath>
#include <cctype>
#include <set>

namespace uvu
{
#define LOCAL ____________DONT_DEFINE_ME____________
#define ll long long
// #define inf 0x3f3f3f3f
// #define int long long
// #define inf 0x3f3f3f3f3f3f3f3fll
#define infll 0x3f3f3f3f3f3f3f3fll
#define debug(...) fprintf(stderr, __VA_ARGS__)
#define gline debug("now is #%d\n", __LINE__)
#define pii std::pair <int, int>
#define mkp std::make_pair
#define fi first
#define se second
char _ST_;
const int BUFSIZE = (1 << 20);
char ibuf[BUFSIZE], *iS = ibuf, *iT = ibuf;
char obuf[BUFSIZE], *oS = obuf, *oT = obuf + BUFSIZE;
char getc()
{
#ifdef LOCAL
	return getchar();
#else
	if(iS == iT) iT = (iS = ibuf) + fread(ibuf, 1, BUFSIZE, stdin);
	return iS == iT ? EOF : *iS++;
#endif
#define getchar ERR
}

void Flush() { fwrite(obuf, 1, oS - obuf, stdout); oS = obuf; }
struct Flusher { ~Flusher(){ Flush(); } }iamflusher;

void putc(char c)
{
#ifdef LOCAL
	putchar(c);
#else
	*oS++ = c;
	if(oS == oT) Flush();
#endif
#define putchar ERR
}

template <typename T = int> T read()
{
	T x = 0, f = 1; char c = getc();
	for(; !isdigit(c); c = getc()) if(c == '-') f = -1;
	for(;  isdigit(c); c = getc()) x = (x << 3) + (x << 1) + (c ^ 48);
	return x * f;
}

template <typename T> void print(T x, char c)
{
static int sta[BUFSIZE], top;
	top = 0;
	if(x < 0) putc('-'), x = -x;
	if(!x) sta[top = 1] = 0;
	for(; x; x /= 10) sta[++top] = x % 10;
	for(; top; ) putc(sta[top--] ^ 48);
	if(c) putc(c);
}

int readstr(char *s, int base)
{
	int idx = base - 1; char c = getc();
	for(; !(isdigit(c) || isalpha(c) || c == '#' || c == '.'); c = getc());
	for(;   isdigit(c) || isalpha(c) || c == '#' || c == '.' ; c = getc()) s[++idx] = c;
	return idx - base + 1;
}

void printf(const char *s) { for(; *s; s++) putc(*s); }
template <typename T, typename ... Args>
void printf(const char *s, T x, Args ... rest)
{
	for(; *s; s++)
	{
		if(*s != '%') { putc(*s); continue; }
		s++; if(*s == 'd') print(x, 0);
		else if(*s == 'c') putc(x);
		printf(s + 1, rest ...);
		return;
	}
}

template <typename T> void ckmax(T &x, T y) { x = x > y ? x : y; }
template <typename T> void ckmin(T &x, T y) { x = x < y ? x : y; }
#define mod 998244353
// #define mod 1000000007
int sm(int x) { return x >= mod ? x - mod : x; }
void plus_(int &x, int y) { x = sm(x + y); }
void mul_(int &x, int y) { x = 1ll * x * y % mod; }
int ksm(int a, int b) { int res = 1; for(; b; b >>= 1, mul_(a, a)) if(b & 1) mul_(res, a); return res; }

#define N 100010
#define M 500010
int n, m, x_[M], y_[M];
int xx[N], yy[N];
namespace T1 { ll dis[N]; int dfn[N], fdfn[N], out[N]; }

namespace T2
{
int h[N], e[N << 1], ne[N << 1], v[N << 1], idx = -1;
void add_edge(int x, int y, int z) { ne[++idx] = h[x], h[x] = idx, e[idx] = y, v[idx] = z; }
void add(int x, int y, int z) { add_edge(x, y, z), add_edge(y, x, z); }
int sz[N], hson[N], top[N], fa[N], dep[N];
ll dis[N];
void dfs0(int k, int fa)
{
	T2::fa[k] = fa; sz[k] = 1; hson[k] = 0; dep[k] = dep[fa] + 1;
	for(int i = h[k]; ~i; i = ne[i]) if(e[i] != fa) 
	{
		dis[e[i]] = dis[k] + v[i], dfs0(e[i], k), sz[k] += sz[e[i]];
		if(sz[e[i]] > sz[hson[k]]) hson[k] = e[i];
	}
}
void dfs1(int k, int tp)
{
	top[k] = tp; if(hson[k]) dfs1(hson[k], tp);
	for(int i = h[k]; ~i; i = ne[i]) if(e[i] != fa[k] && e[i] != hson[k]) dfs1(e[i], e[i]);
}
int LCA(int x, int y) 
{ 
	for(; top[x] != top[y]; x = fa[top[x]]) if(dep[top[x]] < dep[top[y]]) x ^= y ^= x ^= y;
	return dep[x] < dep[y] ? x : y; 
}
ll Dis(int x, int y) { return dis[x] + dis[y] - 2 * dis[LCA(x, y)]; }
void init()
{
	for(int i = 1; i <= n; i++) h[i] = idx = -1;
	for(int i = 1, x, y, z; i < n; i++) x = read(), y = read(), z = read(), add(x, y, z);
	dfs0(1, 0); dfs1(1, 1);
}
struct Tree
{
	int x, y; ll vx, vy, lazy;
	void push(ll z) { vx += z, vy += z, lazy += z; }
}tr[N << 2];
#define root 1, 1, n
#define lson k << 1
#define rson k << 1 | 1
#define ls lson, l, mid
#define rs rson, mid + 1, r
bool ckmax(ll &x, ll y) { if(x <= y) { x = y; return 1; } return 0; }
void pushup(int k) 
{  
	ll mx = -1;
	if(tr[lson].x != tr[lson].y && ckmax(mx, tr[lson].vx + tr[lson].vy + Dis(tr[lson].x, tr[lson].y))) tr[k].x = tr[lson].x, tr[k].y = tr[lson].y, tr[k].vx = tr[lson].vx, tr[k].vy = tr[lson].vy;
	if(tr[rson].x != tr[rson].y && ckmax(mx, tr[rson].vx + tr[rson].vy + Dis(tr[rson].x, tr[rson].y))) tr[k].x = tr[rson].x, tr[k].y = tr[rson].y, tr[k].vx = tr[rson].vx, tr[k].vy = tr[rson].vy;
	if(ckmax(mx, tr[lson].vx + tr[rson].vx + Dis(tr[lson].x, tr[rson].x))) tr[k].x = tr[lson].x, tr[k].y = tr[rson].x, tr[k].vx = tr[lson].vx, tr[k].vy = tr[rson].vx;
	if(ckmax(mx, tr[lson].vx + tr[rson].vy + Dis(tr[lson].x, tr[rson].y))) tr[k].x = tr[lson].x, tr[k].y = tr[rson].y, tr[k].vx = tr[lson].vx, tr[k].vy = tr[rson].vy;
	if(ckmax(mx, tr[lson].vy + tr[rson].vx + Dis(tr[lson].y, tr[rson].x))) tr[k].x = tr[lson].y, tr[k].y = tr[rson].x, tr[k].vx = tr[lson].vy, tr[k].vy = tr[rson].vx;
	if(ckmax(mx, tr[lson].vy + tr[rson].vy + Dis(tr[lson].y, tr[rson].y))) tr[k].x = tr[lson].y, tr[k].y = tr[rson].y, tr[k].vx = tr[lson].vy, tr[k].vy = tr[rson].vy;
}
void pushdown(int k)
{
	if(tr[k].lazy) tr[lson].push(tr[k].lazy), tr[rson].push(tr[k].lazy), tr[k].lazy = 0;
}
void build(int k, int l, int r)
{
	tr[k].lazy = 0;
	if(l == r)
	{
		int p = T1::fdfn[l];
		tr[k].x = tr[k].y = p;
		tr[k].vx = tr[k].vy = T1::dis[p];
		return;
	}
	int mid = (l + r) >> 1; build(ls); build(rs); pushup(k);
}
void change(int k, int l, int r, int ql, int qr, ll z)
{
	if(ql > qr) return;
	if(ql <= l && r <= qr) return tr[k].push(z);
	int mid = (l + r) >> 1; pushdown(k);
	if(ql <= mid) change(ls, ql, qr, z);
	if(mid < qr)  change(rs, ql, qr, z);
	pushup(k);
}
}
namespace T1
{
int h[N], e[N << 1], ne[N << 1], v[N << 1], idx = -1;
void add_edge(int x, int y, int z) { ne[++idx] = h[x], h[x] = idx, e[idx] = y, v[idx] = z; }
void add(int x, int y, int z) { add_edge(x, y, z), add_edge(y, x, z); }
int sz[N], hson[N], top[N], fa[N], dep[N];
void dfs0(int k, int fa)
{
	T1::fa[k] = fa; sz[k] = 1; hson[k] = 0; dep[k] = dep[fa] + 1;
	for(int i = h[k]; ~i; i = ne[i]) if(e[i] != fa) 
	{
		dis[e[i]] = dis[k] + v[i], dfs0(e[i], k), sz[k] += sz[e[i]];
		if(sz[e[i]] > sz[hson[k]]) hson[k] = e[i];
	}
}
void dfs1(int k, int tp)
{
	fdfn[dfn[k] = ++dfn[0]] = k;
	top[k] = tp; if(hson[k]) dfs1(hson[k], tp);
	for(int i = h[k]; ~i; i = ne[i]) if(e[i] != fa[k] && e[i] != hson[k]) dfs1(e[i], e[i]);
	out[k] = dfn[0];
}
int LCA(int x, int y) 
{ 
	for(; top[x] != top[y]; x = fa[top[x]]) if(dep[top[x]] < dep[top[y]]) x ^= y ^= x ^= y;
	return dep[x] < dep[y] ? x : y; 
}
ll Dis(int x, int y) { return dis[x] + dis[y] - 2 * dis[LCA(x, y)]; }
void init()
{
	dfn[0] = 0;
	for(int i = 1; i <= n; i++) h[i] = idx = -1;
	for(int i = 1, x, y, z; i < n; i++) x = read(), y = read(), z = read(), add(x, y, z);
	dfs0(1, 0); dfs1(1, 1);
}

void dfs2(int k, int fa)
{
	xx[k] = T2::tr[1].x, yy[k] = T2::tr[1].y;
	for(int i = h[k]; ~i; i = ne[i]) if(e[i] != fa)
	{
		T2::change(root, dfn[e[i]], out[e[i]], -v[i]);
		T2::change(root, 1, dfn[e[i]] - 1, v[i]);
		T2::change(root, out[e[i]] + 1, n, v[i]);
		dfs2(e[i], k);
		T2::change(root, dfn[e[i]], out[e[i]], v[i]);
		T2::change(root, 1, dfn[e[i]] - 1, -v[i]);
		T2::change(root, out[e[i]] + 1, n, -v[i]);
	}
}

void solve()
{
	dfs2(1, 0); dfs0(1, 0);
}
}

void solve()
{
	// memset(h, idx = -1, sizeof(h));
	n = read();
	T1::init(); T2::init();
	m = read(); for(int i = 1; i <= m; i++) x_[i] = read(), y_[i] = read();
// static int Case;
// 	Case++; if(Case != 3) { for(int i = 1; i <= m; i++) print(-1, '\n'); return; };
	T2::build(root); T1::solve();
	for(int i = 1; i <= m; i++) print(std::max(T2::Dis(xx[x_[i]], y_[i]) + T1::Dis(xx[x_[i]], x_[i]), T2::Dis(yy[x_[i]], y_[i]) + T1::Dis(yy[x_[i]], x_[i])), '\n');
}

void init()
{

}

char _ED_;

void mian()
{
	debug("%.3f MB\n", abs(&_ST_ - &_ED_) / 1024.0 / 1024);
	init();
	for(int T = 1; T; solve(), T--);
}

#ifdef int
	#undef int
#endif
}

int main()
{
	uvu::mian(); return 0;
}

详细

Test #1:

score: 0
Time Limit Exceeded

input:

3 4
1 2 1
2 3 2
1 2 2
2 3 1
1 1
1 2
2 1
2 2

output:


result: