結果
| 問題 | No.3668 Minimum Cut |
| コンテスト | |
| ユーザー |
 miie
|
| 提出日時 | 2026-09-05 00:19:09 |
| 言語 | C++23 (gcc 15.3.0 + boost 1.92.0) |
| 結果 |
WA
|
| 実行時間 | - |
| コード長 | 8,111 bytes |
| 記録 | |
| コンパイル時間 | 3,110 ms |
| コンパイル使用メモリ | 367,116 KB |
| 実行使用メモリ | 9,768 KB |
| 最終ジャッジ日時 | 2026-09-05 00:19:23 |
| 合計ジャッジ時間 | 6,686 ms |
|
ジャッジサーバーID （参考情報） |
judge4_0 / judge3_0 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 38 WA * 1 |
ソースコード
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("avx2")
// 数値型
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using P = pair<int,int>;
using Pll = pair<ll, ll>;
using Pli = pair<ll, int>;
using Pil = pair<int, ll>;
// vector関連
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
template<typename T>
using vc = vector<T>;
template<typename T>
using vvc = vector<vc<T>>;
template<typename T>
using vvvc = vector<vvc<T>>;
template<typename T>
using vvvvc = vector<vvvc<T>>;
// priority_queue
template<typename T>
using pq = priority_queue<T>;
template<typename T>
using pqg = priority_queue<T, vc<T>, greater<T>>;
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define FOR(i, a, b) for(int i = a; i < (int)(b); i++)
#define all(a) (a).begin(),(a).end()
#define rall(a) (a).rbegin(),(a).rend()
#define MIN(vec) *min_element(vec)
#define MAX(vec) *max_element(vec)
#define next_perm(vec) next_permutation((vec).begin(), (vec).end())
#define UNIQUE(vec) vec.erase(unique(vec.begin(), vec.end()), vec.end())
#define el "\n"
#define Yes cout << "Yes" << el
#define No cout << "No" << el
#define YES cout << "YES" << el
#define NO cout << "NO" << el
#define EPS 1e-8
#define Equal(a, b) (fabs((a)-(b)) < EPS)
#define dbg(x) cerr << #x << "=" << x << el
// 定数
const string abc = "abcdefghijklmnopqrstuvwxyz";
const string ABC = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
constexpr int INF = 1001001001;
constexpr ll LINF = 1001001001001001001ll;
constexpr int DX[] = {1, 0, -1, 0};
constexpr int DY[] = {0, 1, 0, -1};
constexpr int DX8[] = {1, 0, -1, 0, 1, 1, -1, -1};
constexpr int DY8[] = {0, 1, 0, -1, 1, -1, 1, -1};
template<typename T1, typename T2>
ostream &operator<< (ostream &os, pair<T1, T2> p) {
os << "{" << p.first << "," << p.second << "}";
return os;
}
template<typename T>
ostream &operator<< (ostream &os, vc<T> &vec) {
int sz = vec.size();
rep(i, sz){
os << vec[i] << (i==sz-1?"":" ");
}
return os;
}
template<typename T1, typename T2>
istream &operator>> (istream &is, pair<T1, T2> &p) {
is >> p.first >> p.second;
return is;
}
template<typename T>
istream &operator>> (istream &is, vc<T> &vec) {
int sz = vec.size();
rep(i, sz) { is >> vec[i]; }
return is;
}
/// @brief aとｂの最大値をaに格納。更新があったかbool値を返す
/// @tparam T1
/// @tparam T2
/// @param a
/// @param b
/// @return bool
template<typename T1, typename T2>
inline bool chmax(T1 &a, T2 b){
bool ret = a<b;
if(ret) a = b;
return ret;
}
/// @brief aとｂの最小値をaに格納。更新があったかbool値を返す
/// @tparam T1
/// @tparam T2
/// @param a
/// @param b
/// @return bool
template<typename T1, typename T2>
inline bool chmin(T1 &a, T2 b){
bool ret = a>b;
if(ret) {a = b;}
return ret;
}
inline void YesNo(bool flag){
if(flag) {Yes;}
else {No;}
return;
}
inline void YESNO(bool flag){
if(flag) {YES;}
else {NO;}
return;
}
inline bool outof(ll x, ll xlim){
return (x<0 || x>=xlim);
}
template<typename T>
inline T sqnorm(T x, T y){
return x*x+y*y;
}
/// @brief char->int
/// @param c
/// @return int
inline int ctoi(char c){
return c-'0';
}
/// @brief xを素因数分解
/// @param x
/// @return vector<Pli>, 素因数の昇順に {p, cnt}
vector<Pli> prime_fact(ll x){
vector<Pli> ret;
for(ll i=2; i*i<=x; i++){
if(x%i == 0){
ret.emplace_back(i, 0);
while(x%i == 0){
ret.back().second++;
x /= i;
}
}
}
if(x != 1) ret.emplace_back(x, 1);
return ret;
}
/// @brief xの約数列挙
/// @param x
/// @return vll, 約数の昇順
vll divisor_enum(ll x){
vector<ll> ret;
for(ll i=1; i*i<=x; i++){
if(x%i == 0){
ret.push_back(x/i);
ret.push_back(i);
}
}
sort(all(ret));
UNIQUE(ret);
return ret;
}
/// @brief 繰り返し二乗法。
/// @tparam T
/// @param x
/// @param k
/// @param op
/// @param e
/// @return
template<typename T>
T pow_t(T x, ll k, T (*op)(T, T), T (*e)()){
T ret = e();
while(k){
if(k&1) ret = op(ret, x);
x = op(x, x);
k >>= 1;
}
return ret;
}
ll powll(ll x, ll k){
return pow_t<ll>(x, k, [](ll a, ll b) -> ll{return a*b;}, []() -> ll{return 1;});
}
inline int pop_cnt(ll x) { return __builtin_popcountll(x); }
inline int top_bit(ll x) { return (x==0?-1:63-__builtin_clzll(x));}
void main2();
int main(){
ios::sync_with_stdio(false);
std::cin.tie(nullptr);
main2();
}
template< typename flow_t >
struct PushRelabel {
const flow_t INF;
struct edge {
int to;
flow_t cap;
int rev;
bool isrev;
int idx;
};
vector< vector< edge > > graph;
vector< flow_t > ex;
int relabels, high;
vector< int > cnt, h;
vector< vector< int > > hs;
PushRelabel(int V) : graph(V), INF(numeric_limits< flow_t >::max()), hs(V + 1), high(0) {}
void add_edge(int from, int to, flow_t cap, int idx = -1) {
graph[from].emplace_back((edge) {to, cap, (int) graph[to].size(), false, idx});
graph[to].emplace_back((edge) {from, 0, (int) graph[from].size() - 1, true, idx});
}
void update_height(int idx, int nxt_height) {
++relabels;
if(h[idx] != graph.size() + 1) {
--cnt[h[idx]];
}
h[idx] = nxt_height;
if(h[idx] != graph.size() + 1) {
high = nxt_height;
++cnt[nxt_height];
if(ex[idx] > 0) hs[nxt_height].emplace_back(idx);
}
}
void global_relabel(int idx) {
for(int i = 0; i <= high; i++) hs[i].clear();
relabels = 0;
high = 0;
h.assign(graph.size(), graph.size() + 1);
cnt.assign(graph.size(), 0);
queue< int > que;
que.emplace(idx);
h[idx] = 0;
while(que.size()) {
int p = que.front();
que.pop();
for(auto &e : graph[p]) {
if(h[e.to] == graph.size() + 1 && graph[e.to][e.rev].cap > 0) {
que.emplace(e.to);
high = h[p] + 1;
update_height(e.to, high);
}
}
}
}
void push(int idx, edge &e) {
if(h[e.to] == graph.size() + 1) return;
if(ex[e.to] == 0) {
hs[h[e.to]].emplace_back(e.to);
}
flow_t df = min(ex[idx], e.cap);
e.cap -= df;
graph[e.to][e.rev].cap += df;
ex[idx] -= df;
ex[e.to] += df;
}
void discharge(int idx) {
int next_height = (int) graph.size() + 1;
for(auto &&e : graph[idx]) {
if(e.cap > 0) {
if(h[idx] == h[e.to] + 1) {
push(idx, e);
if(ex[idx] <= 0) return;
} else {
next_height = min(next_height, h[e.to] + 1);
}
}
}
if(cnt[h[idx]] > 1) {
update_height(idx, next_height);
} else {
for(; high >= h[idx]; hs[high--].clear()) {
for(int j : hs[high]) update_height(j, graph.size() + 1);
}
}
}
flow_t max_flow(int s, int t) {
ex.assign(graph.size(), 0);
ex[s] = INF;
ex[t] = -INF;
global_relabel(t);
for(auto &e : graph[s]) push(s, e);
for(; high >= 0; high--) {
while(!hs[high].empty()) {
int idx = hs[high].back();
hs[high].pop_back();
discharge(idx);
if(relabels >= graph.size() * 4) global_relabel(t);
}
}
return ex[t] + INF;
}
void output() {
for(int i = 0; i < graph.size(); i++) {
for(auto &e : graph[i]) {
if(e.isrev) continue;
auto &rev_e = graph[e.to][e.rev];
cout << i << "->" << e.to << " (flow: " << rev_e.cap << "/" << e.cap + rev_e.cap << ")" << endl;
}
}
}
};
// https://ei1333.github.io/luzhiled/snippets/graph/push-relabel.html
void main2(){
int n, m, s, t;
cin >> n >> m >> s >> t;
PushRelabel<ll> mf(n);
rep(i, m) {
int u, v, c;
cin >> u >> v >> c;
mf.add_edge(u-1, v-1, c);
}
cout << mf.max_flow(s-1, t-1) << el;
}