Files
OI-source/1.1857.cpp
2023-08-03 09:22:52 +08:00

38 lines
826 B
C++

#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
const int maxn=20005;
int n,a,p[maxn],cnt,v[maxn],sg[maxn],step[maxn];
int main()
{
#ifdef local
freopen("pro.in","r",stdin);
#endif
scanf("%d",&n);
for(int i=2;i<maxn;i++) v[i]=i;
for(int i=2;i<maxn;i++)
{
if(v[i]==i) { p[cnt++]=i; }
for(int j=0;j<cnt&&p[j]*i<maxn&&p[j]<=v[i];j++) v[p[j]*i]=p[j];
}
for(int i=2;i<maxn;i++)
{
for(int j=0;j<cnt&&p[j]<=i;j++) if(sg[i-p[j]]==0) sg[i]=1;
if(sg[i]==0) for(int j=0;j<cnt&&p[j]<=i;j++) step[i]=max(step[i-p[j]]+1,step[i]);
else
{
for(int j=0;j<cnt&&p[j]<=i;j++) if(sg[i-p[j]]==0)
{
if(step[i]==0) step[i]=step[i-p[j]]+1;
else step[i]=min(step[i],step[i-p[j]]+1);
}
}
}
for(int i=1;i<=n;i++)
{
scanf("%d",&a);
printf("%d\n",sg[a]?step[a]:-1);
}
return 0;
}