#include<bits/stdc++.h> using namespace std; const int N = ((int)(5e3))+50; const int mod = ((int)(1e9))+7; long long dp[N+50]; int tab[N]; int n; int main(){ ios_base::sync_with_stdio( 0 ); cin.tie( 0 ); cout.tie( 0 ); cin>>n; for (int i = 0; i < n; i++){ cin>>tab[i]; } sort(tab, tab+n); dp[0] = 1; for (int i = 0; i < n; i++){ dp[N] *= 2; if(dp[N] >= mod) dp[N] -= mod; for (int j = N-1; j >= tab[i]-1; j--){ if(j+tab[i] >= N){ dp[N] += dp[j]; if(dp[N] >= mod) dp[N] -= mod; } else { dp[j+tab[i]] += dp[j]; if(dp[j+tab[i]] >= mod) dp[j+tab[i]] -= mod; } } } int ans = 0; for (int i = 1; i <= N; i++){ ans += dp[i]; if(ans >= mod) ans -= mod; } cout<<ans; 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 | #include<bits/stdc++.h> using namespace std; const int N = ((int)(5e3))+50; const int mod = ((int)(1e9))+7; long long dp[N+50]; int tab[N]; int n; int main(){ ios_base::sync_with_stdio( 0 ); cin.tie( 0 ); cout.tie( 0 ); cin>>n; for (int i = 0; i < n; i++){ cin>>tab[i]; } sort(tab, tab+n); dp[0] = 1; for (int i = 0; i < n; i++){ dp[N] *= 2; if(dp[N] >= mod) dp[N] -= mod; for (int j = N-1; j >= tab[i]-1; j--){ if(j+tab[i] >= N){ dp[N] += dp[j]; if(dp[N] >= mod) dp[N] -= mod; } else { dp[j+tab[i]] += dp[j]; if(dp[j+tab[i]] >= mod) dp[j+tab[i]] -= mod; } } } int ans = 0; for (int i = 1; i <= N; i++){ ans += dp[i]; if(ans >= mod) ans -= mod; } cout<<ans; return 0; } |