結果

問題 No.2565 はじめてのおつかい
ユーザー heno239heno239
提出日時 2023-12-20 14:08:56
言語 C++17
(gcc 12.3.0 + boost 1.83.0)
結果
AC  
実行時間 53 ms / 2,000 ms
コード長 6,298 bytes
コンパイル時間 2,125 ms
コンパイル使用メモリ 156,128 KB
実行使用メモリ 18,244 KB
最終ジャッジ日時 2024-09-27 09:50:44
合計ジャッジ時間 5,813 ms
ジャッジサーバーID
（参考情報） 		judge1 / judge2
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 8 ms
11,720 KB
testcase_01 AC 8 ms
11,848 KB
testcase_02 AC 9 ms
11,724 KB
testcase_03 AC 53 ms
18,168 KB
testcase_04 AC 39 ms
18,244 KB
testcase_05 AC 9 ms
11,720 KB
testcase_06 AC 31 ms
13,128 KB
testcase_07 AC 19 ms
12,488 KB
testcase_08 AC 20 ms
12,744 KB
testcase_09 AC 29 ms
12,872 KB
testcase_10 AC 23 ms
12,868 KB
testcase_11 AC 45 ms
15,300 KB
testcase_12 AC 16 ms
12,108 KB
testcase_13 AC 23 ms
12,616 KB
testcase_14 AC 33 ms
14,024 KB
testcase_15 AC 34 ms
13,640 KB
testcase_16 AC 38 ms
16,456 KB
testcase_17 AC 13 ms
12,236 KB
testcase_18 AC 15 ms
13,512 KB
testcase_19 AC 40 ms
14,660 KB
testcase_20 AC 34 ms
14,408 KB
testcase_21 AC 33 ms
14,536 KB
testcase_22 AC 22 ms
13,388 KB
testcase_23 AC 25 ms
13,508 KB
testcase_24 AC 11 ms
12,108 KB
testcase_25 AC 37 ms
14,536 KB
testcase_26 AC 25 ms
13,256 KB
testcase_27 AC 35 ms
14,792 KB
testcase_28 AC 39 ms
14,532 KB
testcase_29 AC 41 ms
15,564 KB
testcase_30 AC 36 ms
15,172 KB
testcase_31 AC 36 ms
14,536 KB
testcase_32 AC 23 ms
13,384 KB
testcase_33 AC 37 ms
15,044 KB
testcase_34 AC 36 ms
14,152 KB
testcase_35 AC 37 ms
15,812 KB
testcase_36 AC 38 ms
14,920 KB
testcase_37 AC 25 ms
13,380 KB
testcase_38 AC 36 ms
14,152 KB
testcase_39 AC 31 ms
13,640 KB
testcase_40 AC 43 ms
15,564 KB
testcase_41 AC 44 ms
15,940 KB
testcase_42 AC 25 ms
13,128 KB
testcase_43 AC 33 ms
14,024 KB
testcase_44 AC 21 ms
12,744 KB
testcase_45 AC 13 ms
12,360 KB
testcase_46 AC 35 ms
13,764 KB
testcase_47 AC 25 ms
12,612 KB
testcase_48 AC 22 ms
12,744 KB
testcase_49 AC 15 ms
12,108 KB
testcase_50 AC 28 ms
12,740 KB
testcase_51 AC 8 ms
11,848 KB
testcase_52 AC 24 ms
12,360 KB
権限があれば一括ダウンロードができます

ソースコード

diff # 

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<unordered_set>
#include<utility>
#include<cassert>
#include<complex>
#include<numeric>
#include<array>
#include<chrono>
using namespace std;

//#define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
//ll mod = 1;
constexpr ll mod = 998244353;
//constexpr ll mod = 1000000009;
const int mod17 = 1000000007;
const ll INF = (ll)mod17 * mod17;
typedef pair<int, int>P;

#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
#define all(v) (v).begin(),(v).end()
typedef pair<ll, ll> LP;

using ld = double;
typedef pair<ld, ld> LDP;
const ld eps = 1e-10;
const ld pi = acosl(-1.0);

template<typename T>
void chmin(T& a, T b) {
	a = min(a, b);
}
template<typename T>
void chmax(T& a, T b) {
	a = max(a, b);
}
template<typename T>
vector<T> vmerge(vector<T>& a, vector<T>& b) {
	vector<T> res;
	int ida = 0, idb = 0;
	while (ida < a.size() || idb < b.size()) {
		if (idb == b.size()) {
			res.push_back(a[ida]); ida++;
		}
		else if (ida == a.size()) {
			res.push_back(b[idb]); idb++;
		}
		else {
			if (a[ida] < b[idb]) {
				res.push_back(a[ida]); ida++;
			}
			else {
				res.push_back(b[idb]); idb++;
			}
		}
	}
	return res;
}
template<typename T>
void cinarray(vector<T>& v) {
	rep(i, v.size())cin >> v[i];
}
template<typename T>
void coutarray(vector<T>& v) {
	rep(i, v.size()) {
		if (i > 0)cout << " "; cout << v[i];
	}
	cout << "\n";
}
ll mod_pow(ll x, ll n, ll m = mod) {
	if (n < 0) {
		ll res = mod_pow(x, -n, m);
		return mod_pow(res, m - 2, m);
	}
	if (abs(x) >= m)x %= m;
	if (x < 0)x += m;
	//if (x == 0)return 0;
	ll res = 1;
	while (n) {
		if (n & 1)res = res * x % m;
		x = x * x % m; n >>= 1;
	}
	return res;
}
//mod should be <2^31
struct modint {
	int n;
	modint() :n(0) { ; }
	modint(ll m) {
		if (m < 0 || mod <= m) {
			m %= mod; if (m < 0)m += mod;
		}
		n = m;
	}
	operator int() { return n; }
};
bool operator==(modint a, modint b) { return a.n == b.n; }
bool operator<(modint a, modint b) { return a.n < b.n; }
modint operator+=(modint& a, modint b) { a.n += b.n; if (a.n >= mod)a.n -= (int)mod; return a; }
modint operator-=(modint& a, modint b) { a.n -= b.n; if (a.n < 0)a.n += (int)mod; return a; }
modint operator*=(modint& a, modint b) { a.n = ((ll)a.n * b.n) % mod; return a; }
modint operator+(modint a, modint b) { return a += b; }
modint operator-(modint a, modint b) { return a -= b; }
modint operator*(modint a, modint b) { return a *= b; }
modint operator^(modint a, ll n) {
	if (n == 0)return modint(1);
	modint res = (a * a) ^ (n / 2);
	if (n % 2)res = res * a;
	return res;
}

ll inv(ll a, ll p) {
	return (a == 1 ? 1 : (1 - p * inv(p % a, a)) / a + p);
}
modint operator/(modint a, modint b) { return a * modint(inv(b, mod)); }
modint operator/=(modint& a, modint b) { a = a / b; return a; }
const int max_n = 1 << 20;
modint fact[max_n], factinv[max_n];
void init_f() {
	fact[0] = modint(1);
	for (int i = 0; i < max_n - 1; i++) {
		fact[i + 1] = fact[i] * modint(i + 1);
	}
	factinv[max_n - 1] = modint(1) / fact[max_n - 1];
	for (int i = max_n - 2; i >= 0; i--) {
		factinv[i] = factinv[i + 1] * modint(i + 1);
	}
}
modint comb(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[b] * factinv[a - b];
}
modint combP(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[a - b];
}

ll gcd(ll a, ll b) {
	a = abs(a); b = abs(b);
	if (a < b)swap(a, b);
	while (b) {
		ll r = a % b; a = b; b = r;
	}
	return a;
}
template<typename T>
void addv(vector<T>& v, int loc, T val) {
	if (loc >= v.size())v.resize(loc + 1, 0);
	v[loc] += val;
}
/*const int mn = 2000005;
bool isp[mn];
vector<int> ps;
void init() {
	fill(isp + 2, isp + mn, true);
	for (int i = 2; i < mn; i++) {
		if (!isp[i])continue;
		ps.push_back(i);
		for (int j = 2 * i; j < mn; j += i) {
			isp[j] = false;
		}
	}
}*/

//[,val)
template<typename T>
auto prev_itr(set<T>& st, T val) {
	auto res = st.lower_bound(val);
	if (res == st.begin())return st.end();
	res--; return res;
}

//[val,)
template<typename T>
auto next_itr(set<T>& st, T val) {
	auto res = st.lower_bound(val);
	return res;
}
using mP = pair<modint, modint>;
mP operator+(mP a, mP b) {
	return { a.first + b.first,a.second + b.second };
}
mP operator+=(mP& a, mP b) {
	a = a + b; return a;
}
mP operator-(mP a, mP b) {
	return { a.first - b.first,a.second - b.second };
}
mP operator-=(mP& a, mP b) {
	a = a - b; return a;
}
LP operator+(LP a, LP b) {
	return { a.first + b.first,a.second + b.second };
}
LP operator+=(LP& a, LP b) {
	a = a + b; return a;
}
LP operator-(LP a, LP b) {
	return { a.first - b.first,a.second - b.second };
}
LP operator-=(LP& a, LP b) {
	a = a - b; return a;
}

mt19937 mt(time(0));

const string drul = "DRUL";
string senw = "SENW";
//DRUL,or SENW
//int dx[4] = { 1,0,-1,0 };
//int dy[4] = { 0,1,0,-1 };

//------------------------------------


void solve() {
	int n, m; cin >> n >> m;
	vector<vector<int>> G(n);
	rep(i, m) {
		int a, b; cin >> a >> b; a--; b--;
		G[a].push_back(b);
	}
	auto get_ds = [&](int s) {
		vector<int> dist(n, mod17/3);
		queue<int> que;
		dist[s] = 0; que.push(s);
		while (!que.empty()) {
			int id = que.front(); que.pop();
			for (int to : G[id]) {
				if (dist[id] + 1 < dist[to]) {
					dist[to] = dist[id] + 1;
					que.push(to);
				}
			}
		}
		return dist;
	};
	auto d0 = get_ds(0);
	auto d1 = get_ds(n-2);
	auto d2 = get_ds(n - 1);
	int ans1 = d0[n - 2] + d1[n - 1] + d2[0];
	int ans2 = d0[n - 1] + d2[n - 2] + d1[0];
	int ans = min(ans1, ans2);
	if (ans >= mod17 / 3)ans = -1;
	cout << ans << "\n";
}



signed main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	//cout << fixed<<setprecision(10);
	//init_f();
	//init();
	//while(true)
	//expr();
	//int t; cin >> t; rep(i, t)
	solve();
	return 0;
}
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