結果
| 問題 |
No.1301 Strange Graph Shortest Path
|
| コンテスト | |
| ユーザー |
 torisasami4
|
| 提出日時 | 2020-11-28 20:51:00 |
| 言語 | C++14 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 541 ms / 3,000 ms |
| コード長 | 9,341 bytes |
| コンパイル時間 | 2,299 ms |
| コンパイル使用メモリ | 192,764 KB |
| 実行使用メモリ | 98,364 KB |
| 最終ジャッジ日時 | 2024-09-13 01:38:55 |
| 合計ジャッジ時間 | 19,310 ms |
|
ジャッジサーバーID （参考情報） |
judge1 / judge4 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 2 |
| other | AC * 33 |
ソースコード
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define pb(x) push_back(x)
#define mp(a, b) make_pair(a, b)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define lscan(x) scanf("%I64d", &x)
#define lprint(x) printf("%I64d", x)
#define rep(i, n) for (ll i = 0; i < (n); i++)
#define rep2(i, n) for (ll i = n - 1; i >= 0; i--)
template <class T>
using rque = priority_queue<T, vector<T>, greater<T>>;
const ll mod = 998244353;
ll gcd(ll a, ll b)
{
ll c = a % b;
while (c != 0)
{
a = b;
b = c;
c = a % b;
}
return b;
}
long long extGCD(long long a, long long b, long long &x, long long &y)
{
if (b == 0)
{
x = 1;
y = 0;
return a;
}
long long d = extGCD(b, a % b, y, x);
y -= a / b * x;
return d;
}
struct UnionFind
{
vector<ll> data;
UnionFind(int sz)
{
data.assign(sz, -1);
}
bool unite(int x, int y)
{
x = find(x), y = find(y);
if (x == y)
return (false);
if (data[x] > data[y])
swap(x, y);
data[x] += data[y];
data[y] = x;
return (true);
}
int find(int k)
{
if (data[k] < 0)
return (k);
return (data[k] = find(data[k]));
}
ll size(int k)
{
return (-data[find(k)]);
}
};
ll M = 1000000007;
vector<ll> fac(2000011); //n!(mod M)
vector<ll> ifac(2000011); //k!^{M-2} (mod M)
ll mpow(ll x, ll n)
{
ll ans = 1;
while (n != 0)
{
if (n & 1)
ans = ans * x % M;
x = x * x % M;
n = n >> 1;
}
return ans;
}
ll mpow2(ll x, ll n, ll mod)
{
ll ans = 1;
while (n != 0)
{
if (n & 1)
ans = ans * x % mod;
x = x * x % mod;
n = n >> 1;
}
return ans;
}
void setcomb()
{
fac[0] = 1;
ifac[0] = 1;
for (ll i = 0; i < 2000010; i++)
{
fac[i + 1] = fac[i] * (i + 1) % M; // n!(mod M)
}
ifac[2000010] = mpow(fac[2000010], M - 2);
for (ll i = 2000010; i > 0; i--)
{
ifac[i - 1] = ifac[i] * i % M;
}
}
ll comb(ll a, ll b)
{
if (a == 0 && b == 0)
return 1;
if (a < b || a < 0)
return 0;
ll tmp = ifac[a - b] * ifac[b] % M;
return tmp * fac[a] % M;
}
ll perm(ll a, ll b)
{
if (a == 0 && b == 0)
return 1;
if (a < b || a < 0)
return 0;
return fac[a] * ifac[a - b] % M;
}
long long modinv(long long a)
{
long long b = M, u = 1, v = 0;
while (b)
{
long long t = a / b;
a -= t * b;
swap(a, b);
u -= t * v;
swap(u, v);
}
u %= M;
if (u < 0)
u += M;
return u;
}
ll modinv2(ll a, ll mod)
{
ll b = mod, u = 1, v = 0;
while (b)
{
ll t = a / b;
a -= t * b;
swap(a, b);
u -= t * v;
swap(u, v);
}
u %= mod;
if (u < 0)
u += mod;
return u;
}
template <int mod>
struct ModInt
{
int x;
ModInt() : x(0) {}
ModInt(int64_t y) : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {}
ModInt &operator+=(const ModInt &p)
{
if ((x += p.x) >= mod)
x -= mod;
return *this;
}
ModInt &operator-=(const ModInt &p)
{
if ((x += mod - p.x) >= mod)
x -= mod;
return *this;
}
ModInt &operator*=(const ModInt &p)
{
x = (int)(1LL * x * p.x % mod);
return *this;
}
ModInt &operator/=(const ModInt &p)
{
*this *= p.inverse();
return *this;
}
ModInt operator-() const { return ModInt(-x); }
ModInt operator+(const ModInt &p) const { return ModInt(*this) += p; }
ModInt operator-(const ModInt &p) const { return ModInt(*this) -= p; }
ModInt operator*(const ModInt &p) const { return ModInt(*this) *= p; }
ModInt operator/(const ModInt &p) const { return ModInt(*this) /= p; }
bool operator==(const ModInt &p) const { return x == p.x; }
bool operator!=(const ModInt &p) const { return x != p.x; }
ModInt inverse() const
{
int a = x, b = mod, u = 1, v = 0, t;
while (b > 0)
{
t = a / b;
swap(a -= t * b, b);
swap(u -= t * v, v);
}
return ModInt(u);
}
ModInt pow(int64_t n) const
{
ModInt ret(1), mul(x);
while (n > 0)
{
if (n & 1)
ret *= mul;
mul *= mul;
n >>= 1;
}
return ret;
}
friend ostream &operator<<(ostream &os, const ModInt &p)
{
return os << p.x;
}
friend istream &operator>>(istream &is, ModInt &a)
{
int64_t t;
is >> t;
a = ModInt<mod>(t);
return (is);
}
static int get_mod() { return mod; }
};
using mint = ModInt<mod>;
typedef vector<vector<mint>> Matrix;
Matrix mul(Matrix a, Matrix b)
{
int i, j, k;
mint t;
int n = a.size(), m = b[0].size(), l = a[0].size();
Matrix c(n, vector<mint>(m));
for (i = 0; i < n; i++)
{
for (j = 0; j < m; j++)
{
t = 0;
for (k = 0; k < l; k++)
t += a[i][k] * b[k][j];
c[i][j] = t;
}
}
return c;
}
Matrix mat_pow(Matrix x, ll n)
{
ll k = x.size();
Matrix ans(k, vector<mint>(k, 0));
for (int i = 0; i < k; i++)
ans[i][i] = 1;
while (n != 0)
{
if (n & 1)
ans = mul(ans, x);
x = mul(x, x);
n = n >> 1;
}
return ans;
}
template <typename flow_t, typename cost_t>
struct PrimalDual
{
const cost_t INF;
bool neg_edge;
struct edge
{
int to;
flow_t cap;
cost_t cost;
int rev;
bool isrev;
};
vector<vector<edge>> graph;
vector<cost_t> potential, min_cost;
vector<int> prevv, preve;
PrimalDual(int V) : graph(V), INF(numeric_limits<cost_t>::max()), neg_edge(false) {}
void add_edge(int from, int to, flow_t cap, cost_t cost)
{
graph[from].emplace_back((edge){to, cap, cost, (int)graph[to].size(), false});
graph[to].emplace_back((edge){from, 0, -cost, (int)graph[from].size() - 1, true});
if(cost < 0)
neg_edge = true;
}
cost_t min_cost_flow(int s, int t, flow_t f)
{
int V = (int)graph.size();
cost_t ret = 0;
using Pi = pair<cost_t, int>;
priority_queue<Pi, vector<Pi>, greater<Pi>> que;
if(neg_edge){
potential.assign(V, INF);
potential[s] = 0;
while (1)
{
bool update = false;
for (int i = 0; i < V; i++)
{
if (potential[i] != INF)
{
for (int j = 0; j < graph[i].size(); j++)
{
edge &e = graph[i][j];
cost_t nextCost = potential[i] + e.cost;
if (e.cap > 0 && potential[e.to] > nextCost)
{
potential[e.to] = nextCost;
update = true;
}
}
}
}
if (!update)
break;
}
}
else
potential.assign(V, 0);
preve.assign(V, -1);
prevv.assign(V, -1);
while (f > 0)
{
min_cost.assign(V, INF);
que.emplace(0, s);
min_cost[s] = 0;
while (!que.empty())
{
Pi p = que.top();
que.pop();
if (min_cost[p.second] < p.first)
continue;
for (int i = 0; i < graph[p.second].size(); i++)
{
edge &e = graph[p.second][i];
cost_t nextCost = min_cost[p.second] + e.cost + potential[p.second] - potential[e.to];
if (e.cap > 0 && min_cost[e.to] > nextCost)
{
min_cost[e.to] = nextCost;
prevv[e.to] = p.second, preve[e.to] = i;
que.emplace(min_cost[e.to], e.to);
}
}
}
if (min_cost[t] == INF)
return -1;
for (int v = 0; v < V; v++)
potential[v] += min_cost[v];
flow_t addflow = f;
for (int v = t; v != s; v = prevv[v])
{
addflow = min(addflow, graph[prevv[v]][preve[v]].cap);
}
f -= addflow;
ret += addflow * potential[t];
for (int v = t; v != s; v = prevv[v])
{
edge &e = graph[prevv[v]][preve[v]];
e.cap -= addflow;
graph[v][e.rev].cap += addflow;
}
}
return ret;
}
vector<pair<pair<int,int>,int>> get_edges()
{
vector<pair<pair<int, int>, int>> E;
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];
E.push_back(mp(mp(i, e.to), rev_e.cap));
}
}
return E;
}
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 << "/" << rev_e.cap + e.cap << ")" << endl;
}
}
}
};
int main()
{
ll n, m;
cin >> n >> m;
PrimalDual<ll, ll> mcf(n+m*2);
ll u, v, c, d;
rep(i, m){
cin >> u >> v >> c >> d;
u--, v--;
mcf.add_edge(u, n + i, 2, 0);
mcf.add_edge(v, n + i, 2, 0);
mcf.add_edge(n + i, n + i + m, 1, c);
mcf.add_edge(n + i, n + i + m, 1, d);
mcf.add_edge(n + i + m, u, 2, 0);
mcf.add_edge(n + i + m, v, 2, 0);
}
cout << mcf.min_cost_flow(0, n-1, 2) << endl;
}