CSES - Putka Open 2020 – 2/5 - Results
Submission details
Task:Torni
Sender:Olli
Submission time:2020-09-26 14:29:08 +0300
Language:C++ (C++11)
Status:READY
Result:100
Feedback
groupverdictscore
#1ACCEPTED15
#2ACCEPTED41
#3ACCEPTED44
Test results
testverdicttimegroup
#1ACCEPTED0.04 s1, 2, 3details
#2ACCEPTED0.04 s2, 3details
#3ACCEPTED0.04 s3details

Code

#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long ll;
const int M = 1e9 + 7;
const int N = 1e6 + 5;
ll ans[N];
ll s[N];
ll po[N];
ll s2[N];
int main() {
po[0] = 1;
po[1] = 1;
for(int i = 2; i < N; ++i) {
po[i] = 4*po[i-1];
po[i] %= M;
}
ans[0] = 1;
s[0] = 1;
for(int i = 1; i < N; ++i) {
if(i <= 3) {
for(int j = 1; j < i; ++j) {
s2[i] += po[j]*s[i-j-1];
s2[i] %= M;
}
} else {
s2[i] = s2[i-1]*4;
s2[i] %= M;
s2[i] += s[i-2];
s2[i] %= M;
}
ans[i] = s[i-1] + s2[i] + po[i];
ans[i] %= M;
s[i] = s[i-1] + ans[i];
s[i] %= M;
}
int t;
cin >> t;
for(int i = 1; i <= t; ++i) {
int n;
cin >> n;
cout << ans[n] << "\n";
}
}

Test details

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

input
10
1
2
3
4
...

correct output
2
8
34
148
650
...

user output
2
8
34
148
650
...

Test 2

Group: 2, 3

Verdict: ACCEPTED

input
100
1
2
3
4
...

correct output
2
8
34
148
650
...

user output
2
8
34
148
650
...
Truncated

Test 3

Group: 3

Verdict: ACCEPTED

input
100
996306
650655
896240
821967
...

correct output
87350005
606189151
122595036
193572715
227926807
...

user output
87350005
606189151
122595036
193572715
227926807
...
Truncated