Acdream 1726 A Math Game

A Math GameTime limit:2000/1000ms (java/others)Memory limit:256000/128000kb (java/others)Submitstatistic Next Problemproblem descriptionrecently, Losanto find an interesting Math game. The rule is Simple:tell you a number H, and you can choose some numbers from a set {a[1],a[2],......, a[n]}. If the sum of the number you choose is H, then you win. Losanto just want to know whether he can win the game. Inputthere is several cases.
In each case, there is numbers in the first line N(The size of the set) and H. The second line has n numbers {a[1],a[2],......, a[n]}. 0<n<=40, 0<=h<10^9, 0<=a[i]<10^9, all the numbers is integers.Outputif Losanto could win the game, output "Yes" in a line. Else output "No" in a line. Sample Input

10 872 3 4 5 7 9 10 11 12 1310 382 3 4 5 7 9 10 11 12 13

Sample Output

NoYes

First store all possible and then search from big to small:

#include <cstdio> #include <cstring> #include <iostream> #include <algorithm>using namespace STD, #include <cstdlib> #include <map> #include <cmath> #include <queue> #include <vector>        #define MAXN 1000000001typedef Long ll;int flag;int a[45];int sum[45];int h;void dfs (int n,int zsum) {if (flag)    Return    if (Zsum>sum[n]) return;        if (Sum[n]==zsum | | zsum==0) {flag=1;    Return              } for (int i=n; i>=1; i--) if (Zsum>=a[i]) {//cout<<zsum<<endl;          DFS (I-1,zsum-a[i]);    }}int Main () {int n,i,j;        while (cin>>n>>h) {flag=0;        sum[0]=0;            for (I=1; i<=n; i++) {cin>>a[i];        Sum[i]=sum[i-1]+a[i];        } dfs (N,H);        if (flag) cout<< "Yes" <<endl;    else cout<< "No" <<endl; } return 0;}

Acdream 1726 A Math game