#include <stdio.h> #include <vector> #include <map> #include <unordered_set> #include <queue> #include <set> #include <unordered_map> #include <math.h> #include <limits.h> #include <algorithm> #include <functional> #include <iterator> #include <algorithm> #include <string> #include <iostream> using namespace std; #define pb push_back #define mp make_pair typedef long long ll; typedef unsigned long long ull; using namespace std; const ll MOD = 1000000007; ll com[300002]; int main() { ios_base::sync_with_stdio(0); cin.tie(NULL); int n, ai; cin >> n; vector<int> numbers; for (int i=0; i<n; ++i) { cin >> ai; numbers.pb(ai); } com[n-1] = 0; com[n] = 1; for (int i=n-1; i>=0; --i) { ll csum = 0; for (int j=i; j<n; ++j) { csum += numbers[j]; if ((csum % MOD) % 2 == 0) { com[i] = (com[i] + com[j+1]) % MOD; } } } cout << com[0] << endl; return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 | #include <stdio.h> #include <vector> #include <map> #include <unordered_set> #include <queue> #include <set> #include <unordered_map> #include <math.h> #include <limits.h> #include <algorithm> #include <functional> #include <iterator> #include <algorithm> #include <string> #include <iostream> using namespace std; #define pb push_back #define mp make_pair typedef long long ll; typedef unsigned long long ull; using namespace std; const ll MOD = 1000000007; ll com[300002]; int main() { ios_base::sync_with_stdio(0); cin.tie(NULL); int n, ai; cin >> n; vector<int> numbers; for (int i=0; i<n; ++i) { cin >> ai; numbers.pb(ai); } com[n-1] = 0; com[n] = 1; for (int i=n-1; i>=0; --i) { ll csum = 0; for (int j=i; j<n; ++j) { csum += numbers[j]; if ((csum % MOD) % 2 == 0) { com[i] = (com[i] + com[j+1]) % MOD; } } } cout << com[0] << endl; return 0; } |