#include <iostream> #include <vector> #include <algorithm> using namespace std; int ps[300300]; int dp[300300]; int M = 1000000007; int main() { int n; scanf("%d",&n); for (int i=1;i<=n;i++) scanf("%d",&ps[i]); for (int i=1;i<=n;i++) { ps[i] += ps[i-1]; if (ps[i] >= M) ps[i] -= M; } dp[0]=1; int r; for (int i=1;i<=n;i++) { for (int j=0;j<i;j++) { r = M + ps[i] - ps[j]; if (r >= M) r-= M; if ((r & 1) == 0) { dp[i] += dp[j]; if (dp[i] >= M) dp[i] -= M; } } } printf("%d\n", 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 | #include <iostream> #include <vector> #include <algorithm> using namespace std; int ps[300300]; int dp[300300]; int M = 1000000007; int main() { int n; scanf("%d",&n); for (int i=1;i<=n;i++) scanf("%d",&ps[i]); for (int i=1;i<=n;i++) { ps[i] += ps[i-1]; if (ps[i] >= M) ps[i] -= M; } dp[0]=1; int r; for (int i=1;i<=n;i++) { for (int j=0;j<i;j++) { r = M + ps[i] - ps[j]; if (r >= M) r-= M; if ((r & 1) == 0) { dp[i] += dp[j]; if (dp[i] >= M) dp[i] -= M; } } } printf("%d\n", dp[n]); } |