#include <bits/stdc++.h> using namespace std; const int p = 1000000007; int main() { ios::sync_with_stdio(0); int n; cin >> n; vector<long long> a(n), sol(n); for(int i=0; i<n; ++i) cin >> a[i]; if(a[0]%2==0) sol[0] = 1; for(int i=1; i<n; ++i) { long long s = 0; int j=i; while(j>0) { s = (s + a[j])%p; --j; if(s%2==0) sol[i] += sol[j]; } s = (s + a[0])%p; if(s%2==0) sol[i] = (sol[i] + 1)%p; } cout << sol[n-1] << endl; }
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 | #include <bits/stdc++.h> using namespace std; const int p = 1000000007; int main() { ios::sync_with_stdio(0); int n; cin >> n; vector<long long> a(n), sol(n); for(int i=0; i<n; ++i) cin >> a[i]; if(a[0]%2==0) sol[0] = 1; for(int i=1; i<n; ++i) { long long s = 0; int j=i; while(j>0) { s = (s + a[j])%p; --j; if(s%2==0) sol[i] += sol[j]; } s = (s + a[0])%p; if(s%2==0) sol[i] = (sol[i] + 1)%p; } cout << sol[n-1] << endl; } |