結果
問題 | No.1865 Make Cycle |
ユーザー | anmichi |
提出日時 | 2022-03-04 22:16:10 |
言語 | C++17 (gcc 12.3.0 + boost 1.83.0) |
結果 |
AC
|
実行時間 | 209 ms / 3,000 ms |
コード長 | 3,265 bytes |
コンパイル時間 | 2,469 ms |
コンパイル使用メモリ | 213,552 KB |
実行使用メモリ | 8,604 KB |
最終ジャッジ日時 | 2023-09-26 01:20:39 |
合計ジャッジ時間 | 6,594 ms |
ジャッジサーバーID (参考情報) |
judge12 / judge13 |
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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 | 146 ms
6,780 KB |
testcase_01 | AC | 83 ms
5,988 KB |
testcase_02 | AC | 161 ms
6,904 KB |
testcase_03 | AC | 40 ms
6,560 KB |
testcase_04 | AC | 97 ms
7,260 KB |
testcase_05 | AC | 143 ms
7,368 KB |
testcase_06 | AC | 138 ms
7,028 KB |
testcase_07 | AC | 118 ms
6,708 KB |
testcase_08 | AC | 184 ms
7,620 KB |
testcase_09 | AC | 138 ms
7,384 KB |
testcase_10 | AC | 151 ms
7,504 KB |
testcase_11 | AC | 143 ms
7,160 KB |
testcase_12 | AC | 121 ms
6,580 KB |
testcase_13 | AC | 131 ms
6,656 KB |
testcase_14 | AC | 94 ms
6,212 KB |
testcase_15 | AC | 168 ms
7,276 KB |
testcase_16 | AC | 191 ms
7,656 KB |
testcase_17 | AC | 126 ms
6,412 KB |
testcase_18 | AC | 144 ms
7,596 KB |
testcase_19 | AC | 209 ms
8,604 KB |
testcase_20 | AC | 2 ms
4,380 KB |
testcase_21 | AC | 2 ms
4,380 KB |
testcase_22 | AC | 2 ms
4,376 KB |
testcase_23 | AC | 1 ms
4,376 KB |
ソースコード
#include <bits/stdc++.h> using namespace std; using ll = long long; #define rep(i, n) for (int i = 0; i < n; i++) #define all(v) v.begin(), v.end() template <class T, class U> inline bool chmax(T& a, U b) { if (a < b) { a = b; return true; } return false; } template <class T, class U> inline bool chmin(T& a, U b) { if (a > b) { a = b; return true; } return false; } constexpr int INF = 1000000000; constexpr ll llINF = 3000000000000000000; constexpr int mod = 998244353; const ll half = (mod + 1) / 2; constexpr double eps = 1e-10; vector<int> prime_list(int n) { vector<int> v(n + 1), res; for (int i = n; i >= 2; i--) { for (int j = i; j <= n; j += i) v[j] = i; } for (int i = 2; i <= n; i++) { if (v[i] == i) res.push_back(i); } return res; } vector<int> next_divisor(int n) { vector<int> v(n + 1); for (int i = n; i >= 2; i--) { for (int j = i; j <= n; j += i) v[j] = i; } return v; } ll modpow(ll a, ll b, ll m = mod) { ll res = 1; while (b) { if (b & 1) { res *= a; res %= m; } a *= a; a %= m; b >>= 1; } return res; } vector<ll> inv, fact, factinv; void init_fact(int n) { inv.resize(n + 1); fact.resize(n + 1); factinv.resize(n + 1); inv[0] = 0; inv[1] = 1; fact[0] = 1; factinv[0] = 1; for (ll i = 1; i <= n; i++) { if (i >= 2) inv[i] = mod - ((mod / i) * inv[mod % i] % mod); fact[i] = (fact[i - 1] * i) % mod; factinv[i] = factinv[i - 1] * inv[i] % mod; } } ll modinv(ll a, ll m = mod) { // gcd(a,m) must be 1 ll b = m, u = 1, v = 0; while (b) { ll 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 comb(int a, int b) { if (a < b || a < 0 || b < 0) return 0; return fact[a] * factinv[a - b] % mod * factinv[b] % mod; } void solve() { int n, q; cin >> n >> q; vector<int> a(q), b(q); rep(i, q) { cin >> a[i] >> b[i]; a[i]--, b[i]--; } int ok = q + 1, ng = 0; while (ok - ng > 1) { int m = (ok + ng) / 2; vector<vector<int>> g(n); vector<int> in(n); vector<bool> vis(n); rep(i, m) { g[a[i]].push_back(b[i]); in[b[i]]++; } queue<int> que; rep(i, n) { if (in[i] == 0) que.push(i); } int res = 0; bool cycle = false; while (!que.empty()) { int p = que.front(); que.pop(); vis[p] = true; for (int i : g[p]) { if (vis[i]) { vis[i] = false; cycle = true; break; } in[i]--; if (in[i] == 0) que.push(i); } if (cycle) break; } if (count(all(vis), true) == n) ng = m; else ok = m; } cout << (ok == q + 1 ? -1 : ok) << endl; } int main() { cin.tie(0); ios::sync_with_stdio(false); /*int t; cin >> t; while (t--)*/ solve(); }