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QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#641044#5. 在线 O(1) 逆元SkyMaths80 5184ms42944kbC++14849b2024-10-14 18:03:142024-11-05 22:06:14

Judging History

你现在查看的是最新测评结果

  • [2024-11-05 22:06:14]
  • 管理员手动重测本题所有提交记录
  • 测评结果:80
  • 用时:5184ms
  • 内存:42944kb
  • [2024-10-14 18:03:18]
  • 评测
  • 测评结果:70
  • 用时:746ms
  • 内存:42940kb
  • [2024-10-14 18:03:14]
  • 提交

answer

#pragma GCC optimize("-Ofast", "-finline", "-funroll-loops", "-fno-stack-protector")
#include<bits/stdc++.h>
// #include "inv.h"
#define rep(i,l,r) for (int i(l), i##end(r); i <= i##end; ++i)
#define per(i,r,l) for (int i(r), i##end(l); i >= i##end; --i)
using namespace std;

const int N = 1e7 + 9, Mod = 998244353;
int n = N - 9, MMI[N];
void init(int p) {
	MMI[1] = 1;
	rep (i, 2, n) MMI[i] = Mod - 1ll * (Mod / i) * MMI[Mod % i] % Mod;
}
int inv(int x) {
	if (x <= n) return MMI[x];
	int q = Mod / x, r = Mod % x;
	if (r < x / 2) return Mod - 1ll * q * inv(r) % Mod;
	return 1ll * (q + 1) * inv(x - r) % Mod;
}

// const int inf = 1e9;
// mt19937 mtrnd(time(0));
// signed main() {
// 	init(Mod);
// 	rep (t, 1, 10) {
// 		int x = mtrnd() % inf + 1;
// 		assert(1ll * x * inv(x) % Mod == 1);
// 	}
// 	return 0;
// }

Details


Pretests


Final Tests

Test #1:

score: 10
Accepted
time: 65ms
memory: 42752kb

Test #2:

score: 20
Accepted
time: 703ms
memory: 42944kb

Test #3:

score: 30
Accepted
time: 3264ms
memory: 42784kb

Test #4:

score: 20
Accepted
time: 5184ms
memory: 42804kb

Test #5:

score: 0
Time Limit Exceeded