#include <cstdio> #include <algorithm> const int N = 5000 + 10, mod = 1e9 + 7; int a[N], dp[2][N]; int main() { int n; scanf("%d", &n); for (int i = 0; i < n; ++i) scanf("%d", &a[i]); std::sort(a, a + n); dp[0][0] = 1; for (int i = 0; i < n; ++i) { int *u = dp[i & 1], *v = dp[(i & 1) ^ 1]; for (int j = 0; j < N; ++j) v[j] = u[j]; for (int j = a[i] - 1; j < N; ++j) if (u[j]) { int k = std::min(j + a[i], N - 1); if ((v[k] += u[j]) >= mod) v[k] -= mod; } } int ret = 0; for (int i = 1; i < N; ++i) { if ((ret += dp[n & 1][i]) >= mod) ret -= mod; } printf("%d\n", ret); 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 | #include <cstdio> #include <algorithm> const int N = 5000 + 10, mod = 1e9 + 7; int a[N], dp[2][N]; int main() { int n; scanf("%d", &n); for (int i = 0; i < n; ++i) scanf("%d", &a[i]); std::sort(a, a + n); dp[0][0] = 1; for (int i = 0; i < n; ++i) { int *u = dp[i & 1], *v = dp[(i & 1) ^ 1]; for (int j = 0; j < N; ++j) v[j] = u[j]; for (int j = a[i] - 1; j < N; ++j) if (u[j]) { int k = std::min(j + a[i], N - 1); if ((v[k] += u[j]) >= mod) v[k] -= mod; } } int ret = 0; for (int i = 1; i < N; ++i) { if ((ret += dp[n & 1][i]) >= mod) ret -= mod; } printf("%d\n", ret); return 0; } |