HDOJ 2682 Tree（最小生成树--prime）

Tree

Time Limit: 6000/2000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 1921    Accepted Submission(s): 561

Problem Description

There are N (2<=N<=600) cities,each has a value of happiness,we consider two cities A and B whose value of happiness are VA and VB,if VA is a prime number,or VB is a prime number or (VA+VB) is a prime number,then they can be connected.What's more,the cost to connecte two cities is Min(Min(VA , VB),|VA-VB|).
Now we want to connecte all the cities together,and make the cost minimal.

 

Input

The first will contain a integer t,followed by t cases.
Each case begin with a integer N,then N integer Vi(0<=Vi<=1000000).

 

Output

If the all cities can be connected together,output the minimal cost,otherwise output "-1";

 

Sample Input

2 5 1 2 3 4 5 4 4 4 4 4

 

Sample Output

4 -1 ac代码：

#include
#include
#include
#include
#include
#define MAXN 10010
#define INF 0xfffffff
#define min(a,b) (a>b?b:a)
using namespace std;
int pri[MAXN][MAXN];
int v[MAXN];
int dis[MAXN];
int n,sum;
int a[MAXN];
int b[10000002];
void fun()  
{  
    int i,j;  
    b[1]=1;  
    for(i=2;i<1000010*2;i++)  
    {  
        if(b[i]==0)
        {  
            for(j=i+i;j<1000010*2;j+=i)  
            {  
                b[j]=1;  
            }  
        }  
    }  
}  
void prime()
{
    int i,j,k;
    int min;
    memset(v,0,sizeof(v));
    for(i=1;i<=n;i++)
    dis[i]=pri[1][i];
    v[1]=1;
    sum=0;
    for(i=0;ipri[k][j])
            dis[j]=pri[k][j];
        }
    }
    if(i