BZOJ 1677 Usaco 求和

 1 #include <cstdio>
 2 #include <algorithm>
 3 #include <cstring>
 4  
 5 typedef long long ll;
 6  
 7 ll n,dp[1000005],tot=9,Out[233];
 8 ll const MOD = 1e9;
 9 
10 int main(){
11     scanf("%lld",&n);
12     dp[0]=1;
13     for(ll i=1;i<=n;i<<=1){
14         for(ll j=1;j<=n;j++){
15             if(j-i>=0) (dp[j]+=dp[j-i])%=MOD;
16         }
17     }
18     printf("%lld\n",dp[n]);
19     return 0;
20 }
21