POJ 2229 Sumsets

 1 /*
 2 @author: Lev
 3 @date:
 4 */
 5 #include <iostream>
 6 #include <cstdio>
 7 #include <cmath>
 8 #include <cstring>
 9 #include <string>
10 #include <cstdlib>
11 #include <algorithm>
12 #include <map>
13 #include <set>
14 #include <queue>
15 #include <climits>
16 #include <deque>
17 #include <sstream>
18 #include <fstream>
19 #include <bitset>
20 #include <iomanip>
21 #define LL long long
22 #define INF 0x3f3f3f3f
23 
24 using namespace std;
25 const int maxn = 1000010;
26 int dp[maxn],c[25] = {1};
27 int main(){
28     int x;
29     for(int i = 1; i < 25; ++i)
30         c[i] = c[i-1]<<1;
31     while(~scanf("%d",&x)){
32         memset(dp,0,sizeof(dp));
33         dp[0] = 1;
34         for(int i = 0;c[i] <= x; ++i){
35             for(int j = c[i]; j <= x; ++j)
36             dp[j] = (dp[j] + dp[j-c[i]])%1000000000;
37         }
38         printf("%d\n",dp[x]);
39     }
40     return 0;
41 }