結果
| 問題 |
No.439 チワワのなる木
|
| ユーザー |
|
| 提出日時 | 2023-12-03 22:50:27 |
| 言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 6,900 bytes |
| コンパイル時間 | 2,130 ms |
| コンパイル使用メモリ | 185,396 KB |
| 実行使用メモリ | 69,776 KB |
| 最終ジャッジ日時 | 2024-09-26 22:21:45 |
| 合計ジャッジ時間 | 4,419 ms |
|
ジャッジサーバーID (参考情報) |
judge1 / judge3 |
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| ファイルパターン | 結果 |
|---|---|
| other | AC * 5 WA * 23 |
コンパイルメッセージ
main.cpp: In lambda function:
main.cpp:242:11: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17' [-Wc++17-extensions]
242 | auto[a,b,c]=x;
| ^
main.cpp:243:11: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17' [-Wc++17-extensions]
243 | auto[d,e,f]=y;
| ^
main.cpp: In lambda function:
main.cpp:250:11: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17' [-Wc++17-extensions]
250 | auto[a,b,c]=x;
| ^
main.cpp: In function 'int main()':
main.cpp:260:11: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17' [-Wc++17-extensions]
260 | auto[A,B,C]=x;
| ^
ソースコード
#include <bits/stdc++.h>
using namespace std;
#define repd(i,a,b) for (ll i=(a);i<(b);i++)
#define rep(i,n) repd(i,0,n)
#define all(x) (x).begin(),(x).end()
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; }
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; }
typedef long long ll;
typedef pair<ll,ll> P;
typedef vector<ll> vec;
using Graph = vector<vector<ll>>;
const long long INF = 1LL<<60;
const long long MOD = 1000000007;
//https://nyaannyaan.github.io/library/graph/graph-template.hpp
template <typename T>
struct edge {
int src, to;
T cost;
edge(int _to, T _cost) : src(-1), to(_to), cost(_cost) {}
edge(int _src, int _to, T _cost) : src(_src), to(_to), cost(_cost) {}
edge &operator=(const int &x) {
to = x;
return *this;
}
operator int() const { return to; }
};
template <typename T>
using Edges = vector<edge<T>>;
template <typename T>
using WeightedGraph = vector<Edges<T>>;
using UnweightedGraph = vector<vector<int>>;
// Input of (Unweighted) Graph
UnweightedGraph graph(int N, int M = -1, bool is_directed = false,
bool is_1origin = true) {
UnweightedGraph g(N);
if (M == -1) M = N - 1;
for (int _ = 0; _ < M; _++) {
int x, y;
cin >> x >> y;
if (is_1origin) x--, y--;
g[x].push_back(y);
if (!is_directed) g[y].push_back(x);
}
return g;
}
// Input of Weighted Graph
template <typename T>
WeightedGraph<T> wgraph(int N, int M = -1, bool is_directed = false,
bool is_1origin = true) {
WeightedGraph<T> g(N);
if (M == -1) M = N - 1;
for (int _ = 0; _ < M; _++) {
int x, y;
cin >> x >> y;
T c;
cin >> c;
if (is_1origin) x--, y--;
g[x].emplace_back(x, y, c);
if (!is_directed) g[y].emplace_back(y, x, c);
}
return g;
}
// Input of Edges
template <typename T>
Edges<T> esgraph(int N, int M, int is_weighted = true, bool is_1origin = true) {
Edges<T> es;
for (int _ = 0; _ < M; _++) {
int x, y;
cin >> x >> y;
T c;
if (is_weighted)
cin >> c;
else
c = 1;
if (is_1origin) x--, y--;
es.emplace_back(x, y, c);
}
return es;
}
// Input of Adjacency Matrix
template <typename T>
vector<vector<T>> adjgraph(int N, int M, T INF, int is_weighted = true,
bool is_directed = false, bool is_1origin = true) {
vector<vector<T>> d(N, vector<T>(N, INF));
for (int _ = 0; _ < M; _++) {
int x, y;
cin >> x >> y;
T c;
if (is_weighted)
cin >> c;
else
c = 1;
if (is_1origin) x--, y--;
d[x][y] = c;
if (!is_directed) d[y][x] = c;
}
return d;
}
/**
* @brief グラフテンプレート
* @docs docs/graph/graph-template.md
*/
//https://nyaannyaan.github.io/library/tree/rerooting.hpp
// Rerooting
// f1(c1, c2) ... merge value of child node
// f2(memo[i], chd, par) ... return value from child node to parent node
// memo[i] ... result of subtree rooted i
// dp[i] ... result of tree rooted i
template <typename T, typename G, typename F1, typename F2>
struct Rerooting {
const G &g;
const F1 f1;
const F2 f2;
vector<T> memo, dp;
T I;
Rerooting(const G &_g, const F1 _f1, const F2 _f2, const T &I_)
: g(_g), f1(_f1), f2(_f2), memo(g.size(), I_), dp(g.size(), I_), I(I_) {
dfs(0, -1);
efs(0, -1, I);
}
const T &operator[](int i) const { return dp[i]; }
void dfs(int cur, int par) {
for (auto &dst : g[cur]) {
if (dst == par) continue;
dfs(dst, cur);
memo[cur] = f1(memo[cur], f2(memo[dst], dst, cur));
}
}
void efs(int cur, int par, const T &pval) {
// get cumulative sum
vector<T> buf;
for (auto dst : g[cur]) {
if (dst == par) continue;
buf.push_back(f2(memo[dst], dst, cur));
}
vector<T> head(buf.size() + 1), tail(buf.size() + 1);
head[0] = tail[buf.size()] = I;
for (int i = 0; i < (int)buf.size(); i++) head[i + 1] = f1(head[i], buf[i]);
for (int i = (int)buf.size() - 1; i >= 0; i--)
tail[i] = f1(tail[i + 1], buf[i]);
// update
dp[cur] = par == -1 ? head.back() : f1(pval, head.back());
// propagate
int idx = 0;
for (auto &dst : g[cur]) {
if (dst == par) continue;
efs(dst, cur, f2(f1(pval, f1(head[idx], tail[idx + 1])), cur, dst));
idx++;
}
}
};
/**
* @brief Rerooting(全方位木DP)
* @docs docs/tree/rerooting.md
*/
// auto mod int
// https://youtu.be/L8grWxBlIZ4?t=9858
// https://youtu.be/ERZuLAxZffQ?t=4807 : optimize
// https://youtu.be/8uowVvQ_-Mo?t=1329 : division
const int mod = 1000000007;
struct mint {
ll x; // typedef long long ll;
mint(ll x=0):x((x%mod+mod)%mod){}
mint operator-() const { return mint(-x);}
mint& operator+=(const mint a) {
if ((x += a.x) >= mod) x -= mod;
return *this;
}
mint& operator-=(const mint a) {
if ((x += mod-a.x) >= mod) x -= mod;
return *this;
}
mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this;}
mint operator+(const mint a) const { return mint(*this) += a;}
mint operator-(const mint a) const { return mint(*this) -= a;}
mint operator*(const mint a) const { return mint(*this) *= a;}
mint pow(ll t) const {
if (!t) return 1;
mint a = pow(t>>1);
a *= a;
if (t&1) a *= *this;
return a;
}
// for prime mod
mint inv() const { return pow(mod-2);}
mint& operator/=(const mint a) { return *this *= a.inv();}
mint operator/(const mint a) const { return mint(*this) /= a;}
};
istream& operator>>(istream& is, mint& a) { return is >> a.x;}
ostream& operator<<(ostream& os, const mint& a) { return os << a.x;}
// combination mod prime
// https://www.youtube.com/watch?v=8uowVvQ_-Mo&feature=youtu.be&t=1619
struct combination {
vector<mint> fact, ifact;
combination(int n):fact(n+1),ifact(n+1) {
assert(n < mod);
fact[0] = 1;
for (int i = 1; i <= n; ++i) fact[i] = fact[i-1]*i;
ifact[n] = fact[n].inv();
for (int i = n; i >= 1; --i) ifact[i-1] = ifact[i]*i;
}
mint operator()(int n, int k) {
if (k < 0 || k > n) return 0;
return fact[n]*ifact[k]*ifact[n-k];
}
mint p(int n,int k){
return fact[n]*ifact[n-k];
}
} C(1000005);
using F=tuple<ll,ll,ll>;
int main()
{
ios::sync_with_stdio(false);
cin.tie(0);
ll n;cin>>n;
string s;cin>>s;
auto g=graph(n,n-1,0,1);
auto f1=[&](F x,F y){
auto[a,b,c]=x;
auto[d,e,f]=y;
c=a*e+b*d;
a+=d;
b+=e;
return F(a,b,c);
};
auto f2=[&](F x,int ch,int p){
auto[a,b,c]=x;
if(s[ch]=='w')a++;
else b++;
return F(a,b,c);
};
Rerooting<F,decltype(g),decltype(f1),decltype(f2)> dp(g,f1,f2,{0,0,0});
ll cnt=0;
rep(i,n)if(s[i]=='w')cnt++;
ll ans=0;
for(auto x:dp.dp){
auto[A,B,C]=x;
ans+=get<2>(x);
}
cout<<ans<<endl;
return 0;
}