QOJ.ac

QOJ

IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#610352#8527. Power DivisionszhouyuhangWA 8ms20412kbC++141.2kb2024-10-04 15:41:112024-10-04 15:41:12

Judging History

你现在查看的是最新测评结果

  • [2024-10-04 15:41:12]
  • 评测
  • 测评结果:WA
  • 用时:8ms
  • 内存:20412kb
  • [2024-10-04 15:41:11]
  • 提交

answer

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

const int N = 3e5 + 10, M = 1e6 + 20, P = 1e9 + 7;
const ll mod = 1e18 + 9;

int n;
int a[N];
ll pw[M];

int s[N], hb; vector<int> pos;
void add(int p) {
	while (s[p]) s[p++] = 0;
	s[p] = 1, hb = max(hb, p);
	pos.push_back(p);
}
void clear() {
	for (auto &p: pos) s[p] = 0;
	hb = 0, pos.clear();
}

vector<int> vec[N];
void solve(int l, int r) {
	if (l == r) {
		vec[r].push_back(l);
		return;
	}
	int mid = (l + r) >> 1;
	solve(l, mid), solve(mid + 1, r);
	unordered_map<ll, int> mp; mp.reserve(r - mid);
	for (ll i = mid + 1, s = pw[a[i]]; i <= r; s = (s + pw[a[++i]]) % P) mp[s] = i;
	clear();
	for (ll i = mid, s = pw[a[i]]; i >= l; s = (s + pw[a[--i]]) % P) {
		add(a[i]); ll v = (pw[hb + 1] + P - s) % P; 
		if (mp.count(v)) vec[mp[v]].push_back(i);
	}
}

int dp[N];

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	cin >> n;
	for (int i = 1; i <= n; ++i) cin >> a[i];
	
	pw[0] = 1;
	for (int i = 1; i <= 1e6 + 18; ++i) pw[i] = 2 * pw[i - 1] % P;
	
	solve(1, n);
	dp[0] = 1;
	for (int i = 1; i <= n; ++i) {
		for (auto &p: vec[i]) dp[i] = (dp[i] + dp[p - 1]) % P;
	}
	cout << dp[n] << endl;

	return 0;
}

Details

Tip: Click on the bar to expand more detailed information

Test #1:

score: 100
Accepted
time: 0ms
memory: 20300kb

input:

5
2 0 0 1 1

output:

6

result:

ok 1 number(s): "6"

Test #2:

score: 0
Accepted
time: 8ms
memory: 20412kb

input:

1
0

output:

1

result:

ok 1 number(s): "1"

Test #3:

score: 0
Accepted
time: 0ms
memory: 19900kb

input:

2
1 1

output:

2

result:

ok 1 number(s): "2"

Test #4:

score: 0
Accepted
time: 7ms
memory: 20164kb

input:

3
2 1 1

output:

3

result:

ok 1 number(s): "3"

Test #5:

score: -100
Wrong Answer
time: 7ms
memory: 20120kb

input:

4
3 2 2 3

output:

3

result:

wrong answer 1st numbers differ - expected: '4', found: '3'