#include <bits/stdc++.h>
using namespace std;
#define MOD 1000000007
#define INF 987654321
typedef long long lld;
// (연속된 짝수개의 0)%2 == (연속된 홀수개의 0)%2
char trace[10];
bool isCorrect(char *s, const int& L){
int i, odd=0, even=0, cnt=0;
int oneCount=0;
for(i=0; i<L; ++i){
if(s[i] == '0'){
cnt = 0;
while(s[i+cnt]=='0') cnt++;
if(cnt&1) odd += 1;
else even += 1;
i += cnt-1;
oneCount += cnt==1;
}
}
if(odd == 1 || even == 1) return false;
if(oneCount&1) return false;
return odd%2 == even%2;
}
lld f(int pos, const int& L){
if(pos == L){
return isCorrect(trace, L);
}
int r = 0;
trace[pos]='0';
r = (r + f(pos+1, L))%MOD;
trace[pos]='1';
r = (r + f(pos+1, L))%MOD;
return r;
}
int main(){
int n;
while(~scanf("%d", &n))
printf("%lld\n", f(0, n));
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
1720 KB |
Output is correct |
2 |
Correct |
0 ms |
1720 KB |
Output is correct |
3 |
Correct |
0 ms |
1720 KB |
Output is correct |
4 |
Correct |
0 ms |
1720 KB |
Output is correct |
5 |
Correct |
0 ms |
1720 KB |
Output is correct |
6 |
Correct |
0 ms |
1720 KB |
Output is correct |
7 |
Incorrect |
0 ms |
1720 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Halted |
0 ms |
0 KB |
- |