#include <bits/stdc++.h> constexpr int MAXN = 3e5 + 10; constexpr int MOPADULO = 1e9 + 7; using namespace std; int n; long long a[MAXN]; long long pref[MAXN]; long long dp[MAXN]; int main() { cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i]; pref[i] = a[i] + pref[i-1]; pref[i] %= MOPADULO; } dp[0] = 1; for (int i = 1; i <= n; i++) { for (int j = 0; j < i; j++) { int q = pref[i] - pref[j]; if (q < 0) q = MOPADULO + q; if (dp[j] == 0 || ((q%MOPADULO)%2) == 1) continue; dp[i] += dp[j]; dp[i] %= MOPADULO; } } cout << dp[n]; }
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 61 62 | #include <bits/stdc++.h> constexpr int MAXN = 3e5 + 10; constexpr int MOPADULO = 1e9 + 7; using namespace std; int n; long long a[MAXN]; long long pref[MAXN]; long long dp[MAXN]; int main() { cin >> n; for (int i = 1; i <= n; i++) { cin >> a[i]; pref[i] = a[i] + pref[i-1]; pref[i] %= MOPADULO; } dp[0] = 1; for (int i = 1; i <= n; i++) { for (int j = 0; j < i; j++) { int q = pref[i] - pref[j]; if (q < 0) q = MOPADULO + q; if (dp[j] == 0 || ((q%MOPADULO)%2) == 1) continue; dp[i] += dp[j]; dp[i] %= MOPADULO; } } cout << dp[n]; } |