# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
959598 | RedGrey1993 | Sailing Race (CEOI12_race) | C++17 | 891 ms | 5716 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
template <typename T1, typename T2> istream &operator>>(istream &is, pair<T1, T2> &pa) { is >> pa.first >> pa.second; return is; }
template <typename T> istream &operator>>(istream &is, vector<T> &vec) { for (auto &v : vec) is >> v; return is; }
template <typename T1, typename T2> ostream &operator<<(ostream &os, const pair<T1, T2> &pa) { os << "(" << pa.first << "," << pa.second << ")"; return os; }
template <typename T> ostream &operator<<(ostream &os, const vector<T> &vec) { os << "["; for (auto v : vec) os << v << ","; os << "]"; return os; }
template <typename T> ostream &operator<<(ostream &os, const deque<T> &vec) { os << "deq["; for (auto v : vec) os << v << ","; os << "]"; return os; }
template <typename T> ostream &operator<<(ostream &os, const set<T> &vec) { os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template <typename T> ostream &operator<<(ostream &os, const multiset<T> &vec) { os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template <typename T> ostream &operator<<(ostream &os, const unordered_set<T> &vec) { os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template <typename T> ostream &operator<<(ostream &os, const unordered_multiset<T> &vec) { os << "{"; for (auto v : vec) os << v << ","; os << "}"; return os; }
template <typename TK, typename TV> ostream &operator<<(ostream &os, const unordered_map<TK, TV> &mp) { os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }
template <typename TK, typename TV> ostream &operator<<(ostream &os, const map<TK, TV> &mp) { os << "{"; for (auto v : mp) os << v.first << "=>" << v.second << ","; os << "}"; return os; }
template <typename T> void resize_array(vector<T> &vec, int len) { vec.resize(len); }
template <typename T, typename... Args> void resize_array(vector<T> &vec, int len, Args... args) { vec.resize(len); for (auto &v : vec) resize_array(v, args...); }
template <typename T1, typename T2> pair<T1, T2> operator+(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first + r.first, l.second + r.second); }
template <typename T1, typename T2> pair<T1, T2> operator-(const pair<T1, T2> &l, const pair<T1, T2> &r) { return make_pair(l.first - r.first, l.second - r.second); }
long long gcd(long long a, long long b) { return b ? gcd(b, a % b) : a; }
mt19937 mrand(random_device{}());
int rnd(int x) { return mrand() % x; }
template <unsigned int MOD>
class ModInt {
public:
ModInt(unsigned long long _v = 0) { set_v((_v % MOD + MOD)); }
explicit operator bool() const { return val != 0; }
ModInt operator-() const { return ModInt() - *this; }
ModInt operator+(const ModInt &r) const { return ModInt().set_v(val + r.val); }
ModInt operator-(const ModInt &r) const { return ModInt().set_v(val + MOD - r.val); }
ModInt operator*(const ModInt &r) const { return ModInt().set_v((unsigned int)((unsigned long long)(val)*r.val % MOD)); }
ModInt operator/(const ModInt &r) const { return *this * r.inv(); }
ModInt &operator+=(const ModInt &r) { return *this = *this + r; }
ModInt &operator-=(const ModInt &r) { return *this = *this - r; }
ModInt &operator*=(const ModInt &r) { return *this = *this * r; }
ModInt &operator/=(const ModInt &r) { return *this = *this / r; }
// ModInt &operator=(unsigned long long _v) { set_v((_v % MOD + MOD)); return *this; }
unsigned int operator=(unsigned long long _v) { set_v((_v % MOD + MOD)); return val; }
bool operator==(const ModInt &r) const { return val == r.val; }
bool operator!=(const ModInt &r) const { return val != r.val; }
ModInt pow(long long n) const {
ModInt x = *this, r = 1;
while (n) {
if (n & 1)
r *= x;
x *= x;
n >>= 1;
}
return r;
}
ModInt inv() const { return pow(MOD - 2); }
unsigned int get_val() { return val; }
friend ostream &operator<<(ostream &os, const ModInt &r) { return os << r.val; }
friend istream &operator>>(istream &is, ModInt &r) { return is >> r.val; }
private:
unsigned int val;
ModInt &set_v(unsigned int _v) {
val = (_v < MOD) ? _v : _v - MOD;
return *this;
}
};
constexpr unsigned int mod = 1e9+7;
using Mint = ModInt<mod>;
#define rep(i, a, n) for (int i = a; i < (n); i++)
#define per(i, a, n) for (int i = (n)-1; i >= a; i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second
#define sz(x) ((int)(x).size())
typedef vector<int> vi;
typedef long long ll;
typedef unsigned int uint;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef double db;
#if DEBUG
#define dbg(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ") " << __FILE__ << endl;
#else
#define dbg(x)
#endif
using Mint2 = ModInt<mod-1>;
template <typename T>
struct Line {
T k, b;
// 集合中的直线按照斜率从小到大排序,该值表示本直线与下一条直线的交点的横坐标
mutable T intersect_x;
bool operator<(const Line<T>& o) const {
return k < o.k;
} // 用于按照斜率排序
bool operator<(T x) const { // 用于在Query时进行二分查找
return intersect_x < x;
} // 用于二分查找
T Eval(T x) const { return k * x + b; } // 求直线在x点的y值
T IntersectX(const Line<T>& line) const { // 求与直线line的交点的横坐标
assert(k != line.k); // 斜率不能相等,否则除0异常
return Div(line.b - b, k - line.k);
}
T Div(T a, T b) const {
if constexpr (std::is_integral<T>::value) {
// floored division,
// 因为两条直线之间的交点可能是小数,但是x是整数,因此小数部分永远不会取到
// 所以求直线交点时只需要记录<=交点横坐标值的最大整数即可
// 3/2 -> 1; -3/2 -> -2; 4/2 -> 2; -4/2 -> 2
return a / b - ((a ^ b) < 0 && a % b);
} else {
return a / b;
}
}
};
template <typename T>
class LichaoTree {
struct Node {
Line<T> line{0, numeric_limits<T>::max()};
int left = -1, right = -1;
};
public:
LichaoTree(T mint, T maxt) {
mint_ = mint;
maxt_ = maxt;
}
void Add(const Line<T>& line) {
Add(line, root_, mint_, maxt_);
}
T Query(T x) {
return Query(x, 0, mint_, maxt_);
}
private:
void Add(Line<T> line, int& v, T l, T r) {
if (v == -1) {
v = trees.size();
trees.emplace_back(Node{line, -1, -1});
return;
}
T m = l + (r - l) / 2;
bool lef = line.Eval(l) < trees[v].line.Eval(l);
bool mid = line.Eval(m) < trees[v].line.Eval(m);
bool rht = line.Eval(r) < trees[v].line.Eval(r);
if (mid) {
swap(trees[v].line, line);
}
if ((lef && rht) || (!lef && !rht)) {
return;
} else if (lef != mid) {
Add(line, trees[v].left, l, m);
} else {
Add(line, trees[v].right, m, r);
}
}
T Query(T x, int v, T l, T r) {
if (v == -1) return numeric_limits<T>::max();
T m = l + (r - l) / 2;
if (x < m) {
return min(trees[v].line.Eval(x), Query(x, trees[v].left, l, m));
} else {
return min(trees[v].line.Eval(x), Query(x, trees[v].right, m, r));
}
}
T mint_,maxt_;
vector<Node> trees;
int root_ = -1;
};
class Solution {
public:
void Solve() {
int n,op;
while(cin>>n>>op) {
vector<vi> edges(n+1);
vector<vi> has_edge(n+1, vi(n+1, 0));
rep(from,1,n+1) {
int to;
while(cin>>to) {
if (to == 0) break;
edges[from].emplace_back(to);
has_edge[from][to] = 1;
}
}
// c -> clockwise, cc -> counter_clockwise
vector<vi> dp_c(n+1, vi(n+1, -1)), dp_cc(n+1, vi(n+1, -1));
// is s<k<e ?
auto between_range = [&] (int k, int s, int e, bool clockwise) {
if (clockwise) swap(s, e);
if (s==e) return k!=s;
int d1 = k-s; if (d1<0) d1 += n;
int d2 = e-s; if (d2<0) d2 += n;
return k!=s && d1 < d2;
};
function<int(int,int)> dfs_c,dfs_cc;
// [i,j)
// dp_c[i][j] = 1 + max(dp_c[k][j], dp_cc[k][i]) exists(i->k, j<k<i)
// dp_cc[i][j] = 1 + max(dp_cc[k][j], dp_c[k][i]) exists(i->k, i<k<j)
dfs_c = [&] (int i, int j) -> int {
if (dp_c[i][j] != -1) return dp_c[i][j];
dp_c[i][j] = 0;
for (int k : edges[i]) {
if (between_range(k, i, j, true)) {
dp_c[i][j] = max(dp_c[i][j], 1 + max(dfs_c(k, j), dfs_cc(k, i)));
}
}
return dp_c[i][j];
};
dfs_cc = [&] (int i, int j) -> int {
if (dp_cc[i][j] != -1) return dp_cc[i][j];
dp_cc[i][j] = 0;
for (int k : edges[i]) {
if (between_range(k, i, j, false)) {
dp_cc[i][j] = max(dp_cc[i][j], 1 + max(dfs_cc(k, j), dfs_c(k, i)));
}
}
return dp_cc[i][j];
};
int ans = 0, st = 0;
rep(i,1,n+1) {
if (dfs_cc(i, i) > ans) {
ans = dfs_cc(i, i);
st = i;
}
}
// dbg(dp_c);
// dbg(dp_cc);
if (op) {
vector<vi> dp_succ_c(n+1, vi(n+1, -1)), dp_succ_cc(n+1, vi(n+1, -1));
function<int(int,int)> dfs_succ_c = [&] (int i, int j) -> int {
if (i==j) return dp_succ_c[i][j]=0;
if (dp_succ_c[i][j] != -1) return dp_succ_c[i][j];
dp_succ_c[i][j] = -2;
for (int k : edges[i]) {
if ((k==j||between_range(k, i, j, true)) && dfs_succ_c(k, j) >= 0) {
dp_succ_c[i][j] = max(dp_succ_c[i][j], 1 + dfs_succ_c(k, j));
}
}
return dp_succ_c[i][j];
};
rep(i,1,n+1) {
rep(j,1,n+1) dfs_succ_c(i,j);
}
function<int(int,int)> dfs_succ_cc = [&] (int i, int j) -> int {
if (i==j) return dp_succ_cc[i][j]=0;
if (dp_succ_cc[i][j] != -1) return dp_succ_cc[i][j];
dp_succ_cc[i][j] = -2;
for (int k : edges[i]) {
if ((k==j||between_range(k, i, j, false)) && dfs_succ_cc(k, j) >= 0) {
dp_succ_cc[i][j] = max(dp_succ_cc[i][j], 1 + dfs_succ_cc(k, j));
}
}
return dp_succ_cc[i][j];
};
rep(i,1,n+1) {
rep(j,1,n+1) dfs_succ_cc(i,j);
}
// dbg(dp_succ_c);
// dbg(dp_succ_cc);
vi ansv(n+1);
// ans[i] = max(1+dp_succ_c[j][k]+1+max(dp_c[l][j], dp_cc[l][i])) exists(k->l, j<l<i), dp_succ_c[j][k]!=0
rep(j,1,n+1) {
int i = j + 1, k = i + 1;
if (i > n) i -= n; if (k > n) k-=n;
while(true) {
if (has_edge[i][j]) {
if (dp_succ_c[j][k] > 0) {
for (int l:edges[k]) {
if (between_range(l,i,j,true)) ansv[i] = max(ansv[i], 1+dp_succ_c[j][k]+1+max(dp_c[l][j], dp_cc[l][i]));
}
}
if (has_edge[k][j]) i = k;
k++; if (k > n) k-=n;
} else {
i++; k=i+1;
if (i > n) i -= n; if (k > n) k-=n;
}
if (k==j) break;
if (i==j) break;
}
}
// ans[i] = max(1+dp_succ_cc[j][k]+1+max(dp_cc[l][j], dp_c[l][i])) exists(k->l, i<l<j), dp_succ_cc[j][k]!=0
rep(j,1,n+1) {
int i = j - 1, k = i - 1;
if (i < 1) i += n; if (k < 1) k+=n;
while(true) {
if (has_edge[i][j]) {
if (dp_succ_cc[j][k] > 0) {
for (int l:edges[k]) {
if (between_range(l,i,j,false)) ansv[i] = max(ansv[i], 1+dp_succ_cc[j][k]+1+max(dp_cc[l][j], dp_c[l][i]));
}
}
if (has_edge[k][j]) i = k;
k--; if (k < 1) k+=n;
} else {
i--; k=i-1;
if (i < 1) i += n; if (k < 1) k+=n;
}
if (k==j) break;
if (i==j) break;
}
}
// dbg(ansv);
// ans = 0; st = 0;
rep(i,1,n+1) if (ansv[i]>ans) {
ans = ansv[i];
st = i;
}
}
cout << ans << endl;
cout << st << endl;
}
}
private:
};
// #define USACO 1
void set_io(const string &name = "") {
ios::sync_with_stdio(false);
cin.tie(nullptr);
#if FILE_IO || USACO
if (!name.empty()) {
freopen((name + ".in").c_str(), "r", stdin);
freopen((name + ".out").c_str(), "w", stdout);
}
#endif
}
int main() {
#if USACO
set_io("time");
#else
set_io("tmp");
#endif
Solution().Solve();
return 0;
}
Compilation message (stderr)
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