/*************************************
* author: marvinthang *
* created: 05.12.2023 08:26:16 *
*************************************/
#include <bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define left ___left
#define right ___right
#define TIME (1.0 * clock() / CLOCKS_PER_SEC)
#define MASK(i) (1LL << (i))
#define BIT(x, i) ((x) >> (i) & 1)
#define __builtin_popcount __builtin_popcountll
#define ALL(v) (v).begin(), (v).end()
#define REP(i, n) for (int i = 0, _n = (n); i < _n; ++i)
#define REPD(i, n) for (int i = (n); i-- > 0; )
#define FOR(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define FORD(i, b, a) for (int i = (b), _a = (a); --i >= _a; )
#define FORE(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORDE(i, b, a) for (int i = (b), _a = (a); i >= _a; --i)
#define scan_op(...) istream & operator >> (istream &in, __VA_ARGS__ &u)
#define print_op(...) ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
#include "debug.h"
#else
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
#define DB(...) 23
#define db(...) 23
#define debug(...) 23
#endif
template <class U, class V> scan_op(pair <U, V>) { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>) { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>) { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")"; else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }
const int MOD = 1e9 + 7;
namespace MODULAR {
inline void fasterLLDivMod(unsigned long long x, unsigned y, unsigned &out_d, unsigned &out_m) {
unsigned xh = (unsigned)(x >> 32), xl = (unsigned)x, d, m;
#ifdef __GNUC__
asm(
"divl %4 \n\t"
: "=a" (d), "=d" (m)
: "d" (xh), "a" (xl), "r" (y)
);
#else
__asm {
mov edx, dword ptr[xh];
mov eax, dword ptr[xl];
div dword ptr[y];
mov dword ptr[d], eax;
mov dword ptr[m], edx;
};
#endif
out_d = d; out_m = m;
}
template <class T> T invGeneral(T a, T b) {
a %= b;
if (!a) return b == 1 ? 0 : -1;
T x = invGeneral(b, a);
return x == -1 ? -1 : ((1 - 1LL * b * x) / a + b) % b;
}
template <int MOD> struct ModInt {
unsigned int val;
ModInt(void): val(0) {}
ModInt(const long long &x) { *this = x; }
ModInt & normalize(const unsigned int &v) {
val = v >= MOD ? v - MOD : v;
return *this;
}
bool operator ! (void) { return !val; }
ModInt & operator = (const ModInt &x) { val = x.val; return *this; }
ModInt & operator = (const long long &x) { return normalize(x % MOD + MOD); }
ModInt operator - (void) { return ModInt(MOD - val); }
ModInt & operator += (const ModInt &other) { return normalize(val + other.val); }
ModInt & operator -= (const ModInt &other) { return normalize(val + MOD - other.val); }
ModInt & operator /= (const ModInt &other) { return *this *= other.inv(); }
ModInt & operator *= (const ModInt &other) {
unsigned dummy;
fasterLLDivMod((unsigned long long) val * other.val, MOD, dummy, val);
return *this;
}
ModInt operator + (const ModInt &other) const { return ModInt(*this) += other; }
ModInt operator - (const ModInt &other) const { return ModInt(*this) -= other; }
ModInt operator * (const ModInt &other) const { return ModInt(*this) *= other; }
ModInt operator / (const ModInt &other) const { return ModInt(*this) /= other; }
ModInt pow(long long n) const {
assert(n >= 0);
ModInt res = 1, a = *this;
for (; n; n >>= 1, a *= a) if (n & 1) res *= a;
return res;
}
ModInt inv(void) const {
int i = invGeneral((int) val, MOD);
assert(~i);
return i;
}
ModInt & operator ++ (void) { return *this += 1; }
ModInt & operator -- (void) { return *this -= 1; }
ModInt operator ++ (int) { ModInt old = *this; operator ++(); return old; }
ModInt operator -- (int) { ModInt old = *this; operator --(); return old; }
friend ModInt operator + (const long long &x, const ModInt &y) { return ModInt(x) + y; }
friend ModInt operator - (const long long &x, const ModInt &y) { return ModInt(x) - y; }
friend ModInt operator * (const long long &x, const ModInt &y) { return ModInt(x) * y; }
friend ModInt operator / (const long long &x, const ModInt &y) { return ModInt(x) / y; }
friend ostream & operator << (ostream &out, const ModInt &x) { return out << x.val; }
friend istream & operator >> (istream &in, ModInt &x) { long long a; in >> a; x = a; return in; }
explicit operator bool(void) const { return val; }
explicit operator int(void) const { return val; }
};
using Modular = ModInt <MOD>;
}
using namespace MODULAR;
// end of template
void process(void) {
int n, r; cin >> n >> r;
vector <vector <int>> adj(n);
REP(i, n - 1) {
int u, v; cin >> u >> v; --u; --v;
adj[u].push_back(v);
adj[v].push_back(u);
}
vector <int> tags(n, -1);
tags[0] = r;
int m = n + r;
vector <Modular> fact(m + 1), ifact(m + 1);
fact[0] = 1;
FORE(i, 1, m) fact[i] = fact[i - 1] * i;
ifact[m] = fact[m].inv();
REPD(i, m) ifact[i] = ifact[i + 1] * (i + 1);
auto C = [&] (int n, int k) -> Modular {
if (k < 0 || n < k) return 0;
return fact[n] * ifact[k] * ifact[n - k];
};
auto candy = [&] (int n, int k) {
return C(n + k - 1, k - 1);
};
Modular res;
vector <int> tsz(n);
function<void(int)> dfs = [&] (int u) {
tsz[u] = 1;
for (int v: adj[u]) {
adj[v].erase(find(ALL(adj[v]), u));
dfs(v);
tsz[u] += tsz[v];
}
};
dfs(0);
function<pair<int, int>(int)> solve = [&] (int u) {
int st = 0, sz = 0;
for (int v: adj[u]) {
auto [x, y] = solve(v);
st += x; sz += y;
if (st > r) {
res = 0;
return pair{0, 0};
}
}
if (tags[u] >= 0) {
res *= candy(tags[u] - st, tsz[u] - sz);
return pair{tags[u], tsz[u] - sz};
}
return pair{st, sz};
};
res = 1;
solve(0);
cout << res << '\n';
int q; cin >> q;
while (q--) {
int t, u; cin >> t >> u; --u;
if (t == 1) {
cin >> t;
tags[u] = t;
} else tags[u] = -1;
res = 1;
solve(0);
cout << res << '\n';
}
}
int main(void) {
ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
file("INOI20_sumtree");
// int t; cin >> t; while (t--)
process();
// cerr << "Time elapsed: " << TIME << " s.\n";
return (0^0);
}
Compilation message
Main.cpp: In function 'int main()':
Main.cpp:30:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
30 | #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:191:2: note: in expansion of macro 'file'
191 | file("INOI20_sumtree");
| ^~~~
Main.cpp:30:94: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
30 | #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:191:2: note: in expansion of macro 'file'
191 | file("INOI20_sumtree");
| ^~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
94 ms |
30032 KB |
Output is correct |
| 2 |
Correct |
95 ms |
29008 KB |
Output is correct |
| 3 |
Correct |
112 ms |
28744 KB |
Output is correct |
| 4 |
Correct |
116 ms |
29632 KB |
Output is correct |
| 5 |
Correct |
77 ms |
24148 KB |
Output is correct |
| 6 |
Correct |
6 ms |
3164 KB |
Output is correct |
| 7 |
Correct |
6 ms |
2908 KB |
Output is correct |
| 8 |
Correct |
3 ms |
1748 KB |
Output is correct |
| 9 |
Correct |
72 ms |
19172 KB |
Output is correct |
| 10 |
Correct |
111 ms |
19476 KB |
Output is correct |
| 11 |
Correct |
73 ms |
19540 KB |
Output is correct |
| 12 |
Correct |
65 ms |
16708 KB |
Output is correct |
| 13 |
Correct |
84 ms |
28244 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3030 ms |
29060 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
3012 ms |
19660 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
94 ms |
30032 KB |
Output is correct |
| 2 |
Correct |
95 ms |
29008 KB |
Output is correct |
| 3 |
Correct |
112 ms |
28744 KB |
Output is correct |
| 4 |
Correct |
116 ms |
29632 KB |
Output is correct |
| 5 |
Correct |
77 ms |
24148 KB |
Output is correct |
| 6 |
Correct |
6 ms |
3164 KB |
Output is correct |
| 7 |
Correct |
6 ms |
2908 KB |
Output is correct |
| 8 |
Correct |
3 ms |
1748 KB |
Output is correct |
| 9 |
Correct |
72 ms |
19172 KB |
Output is correct |
| 10 |
Correct |
111 ms |
19476 KB |
Output is correct |
| 11 |
Correct |
73 ms |
19540 KB |
Output is correct |
| 12 |
Correct |
65 ms |
16708 KB |
Output is correct |
| 13 |
Correct |
84 ms |
28244 KB |
Output is correct |
| 14 |
Incorrect |
0 ms |
348 KB |
Output isn't correct |
| 15 |
Halted |
0 ms |
0 KB |
- |
