Submission #1110350
Source Code Expand
#include <cstdio>
#include <iostream>
#include <vector>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <string>
#include <cstring>
#include <sstream>
#include <algorithm>
#include <functional>
#include <queue>
#include <stack>
#include <cmath>
#include <iomanip>
#include <list>
#include <tuple>
#include <bitset>
#include <ciso646>
#include <cassert>
using namespace std;
#define int long long
#define double long double
typedef pair<int, int> P;
typedef tuple<int, int, int> T;
template<class T> string tostr(T x) { stringstream o; o << x; return o.str(); }
template<class T> T sqr(T x) { return x*x; }
template<class T> T mypow(T x, int n) { T r = 1; while (n > 0) { if (n & 1)r = r*x; x = x*x; n >>= 1; }return r; }
int toint(string s) { int v; stringstream i(s); i >> v; return v; }
bool check(int x, int y, int w, int h) { return x >= 0 && y >= 0 && w > x && h > y; }
int gcd(int a, int b) { return b ? gcd(b, a%b) : a; }
int lcm(int a, int b) { return a / gcd(a, b) * b; }
#define REP(i,a,b) for(int (i) = (a);i < (b);(i)++)
#define rep(i,n) REP(i,0,n)
#define PER(i,a,b) for(int (i) = (a-1);i >= (b);(i)--)
#define per(i,n) PER(i,n,0)
#define each(i,n) for(auto &i : n)
#define clr(a) memset((a), 0 ,sizeof(a))
#define mclr(a) memset((a), -1 ,sizeof(a))
#define all(a) (a).begin(),(a).end()
#define dump(val) cerr << #val " = " << val << endl;
#define dum(val) cerr << #val " = " << val;
#define FILL(a,v) fill(a,a+sizeof(a)/sizeof(*a),v)
const int dx[8] = { +1,+0,-1,+0,+1,+1,-1,-1 };
const int dy[8] = { +0,-1,+0,+1,-1,+1,-1,+1 };
const int mod = 1e9 + 7;
const int INF = 1e17 + 9;
int mod_pow(int x, int n, int mod) {
int res = 1;
while (n > 0) {
if (n & 1)res = res * x % mod;
x = x * x % mod;
n >>= 1;
}
return res;
}
signed main() {
cin.tie(0);
ios_base::sync_with_stdio(false);
int n;
cin >> n;
map<int, int> mp;
for (int i = 0; i < n; i++) {
int a;
cin >> a;
mp[a]++;
}
auto zero = [&]() {
cout << 0 << endl; exit(0);
};
if (n % 2) {
if (mp[0] != 1) zero();
for (int i = 2; i <= n - 1; i += 2) {
if (mp[i] != 2)zero();
}
}
else {
for (int i = 1; i <= n - 1; i += 2) {
if (mp[i] != 2)zero();
}
}
cout << mod_pow(2, n / 2, mod) << endl;
return 0;
}
Submission Info
Submission Time |
|
Task |
C - Lining Up |
User |
omu |
Language |
C++14 (GCC 5.4.1) |
Score |
300 |
Code Size |
2372 Byte |
Status |
AC |
Exec Time |
39 ms |
Memory |
4224 KB |
Judge Result
Set Name |
Sample |
All |
Score / Max Score |
0 / 0 |
300 / 300 |
Status |
|
|
Set Name |
Test Cases |
Sample |
sample_01.txt, sample_02.txt, sample_03.txt |
All |
subtask_1_invalid_01.txt, subtask_1_invalid_02.txt, subtask_1_max_01.txt, subtask_1_max_02.txt, subtask_1_max_valid_01.txt, subtask_1_max_valid_02.txt, subtask_1_min_valid_01.txt, subtask_1_rand_01.txt, subtask_1_rand_02.txt, subtask_1_valid_01.txt, subtask_1_valid_02.txt |
Case Name |
Status |
Exec Time |
Memory |
sample_01.txt |
AC |
3 ms |
256 KB |
sample_02.txt |
AC |
3 ms |
256 KB |
sample_03.txt |
AC |
3 ms |
256 KB |
subtask_1_invalid_01.txt |
AC |
29 ms |
2944 KB |
subtask_1_invalid_02.txt |
AC |
7 ms |
768 KB |
subtask_1_max_01.txt |
AC |
37 ms |
4224 KB |
subtask_1_max_02.txt |
AC |
37 ms |
4224 KB |
subtask_1_max_valid_01.txt |
AC |
39 ms |
3328 KB |
subtask_1_max_valid_02.txt |
AC |
39 ms |
3328 KB |
subtask_1_min_valid_01.txt |
AC |
3 ms |
256 KB |
subtask_1_rand_01.txt |
AC |
22 ms |
2688 KB |
subtask_1_rand_02.txt |
AC |
34 ms |
3840 KB |
subtask_1_valid_01.txt |
AC |
21 ms |
1920 KB |
subtask_1_valid_02.txt |
AC |
9 ms |
896 KB |