hdu4277 数字的hash

容器的应用

hdu4277

#include<iostream>#include<vector>#include<cstdio>using namespace std;typedef long long lld;const int MOD=10003;vector<lld> v[MOD+10];int num,n,i,N[15];void insert(lld x){int key=x%MOD;for(i=0;i<v[key].size();i++)if(v[key][i]==x)return;v[key].push_back(x);num++;}void dfs(int a,int b,int c,int id) //三个木棍的枚举，参数分别是a,b,c及当前已用去得数量{if(id==n){if(a<=b&&b<=c&&a+b>c)insert(a*1000000000000LL+b*1000000+c);return ;}dfs(a+N[id],b,c,id+1);dfs(a,b+N[id],c,id+1);dfs(a,b,c+N[id],id+1);}int main(){int T;scanf("%d",&T);while(T--){scanf("%d",&n);for(i=0;i<n;i++)scanf("%d",N+i);for(i=0;i<MOD;i++)v[i].clear();num=0;dfs(0,0,0,0);printf("%d\n",num);}return 0;}