Solution
2023-07-18 14:37:52
发布于:广东
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#define _USE_MATH_DEFINES
#include <bits/extc++.h>
#define PI M_PI
#define E M_E
#define npt nullptr
#define SON i->to
#define OPNEW void* operator new(size_t)
#define ROPNEW(arr) void* Edge::operator new(size_t){static Edge* P = arr; return P++;}
using namespace std;
using namespace __gnu_pbds;
mt19937 rnd(random_device{}());
int rndd(int l, int r){return rnd() % (r - l + 1) + l;}
bool rnddd(int x){return rndd(1, 100) <= x;}
typedef unsigned int uint;
typedef unsigned long long unll;
typedef long long ll;
typedef long double ld;
template< typename T = int >
inline T read(void);
struct Edge{
Edge* nxt;
int to;
int val;
OPNEW;
}ed[11000];
ROPNEW(ed);
Edge* head[5100];
vector < int > vert[5100];
int N, Q;
void dfs(int rt, int p, int fa = 0, int cur = 0){
if(cur)vert[rt].emplace_back(cur);
for(auto i = head[p]; i; i = i->nxt)
if(SON != fa)dfs(rt, SON, p, cur ? min(cur, i->val) : i->val);
}
int main(){
N = read(), Q = read();
for(int i = 1; i <= N - 1; ++i){
int s = read(), t = read(), val = read();
head[s] = new Edge{head[s], t, val};
head[t] = new Edge{head[t], s, val};
}
for(int i = 1; i <= N; ++i)dfs(i, i), sort(vert[i].begin(), vert[i].end());
while(Q--){
int dis = read(), p = read();
printf("%d\n", (int)distance(lower_bound(vert[p].begin(), vert[p].end(), dis), vert[p].end()));
}
return 0;
}
template < typename T >
inline T read(void){
T ret(0);
short flag(1);
char c = getchar();
while(c != '-' && !isdigit(c))c = getchar();
if(c == '-')flag = -1, c = getchar();
while(isdigit(c)){
ret *= 10;
ret += int(c - '0');
c = getchar();
}
ret *= flag;
return ret;
}
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