素数对猜想及线性表链式存储

1.线性表链式存储

https://github.com/BodhiXing/Data_Structure

2.素数对猜想

https://pta.patest.cn/pta/test/17/exam/4/question/261

思路：查找小于N的素数，存入数组，若相邻的相差2，则计数加1。

 1 #include <stdio.h>
 2 #include <math.h>
 3 
 4 #define MAX 100000
 5 int a[MAX];
 6 
 7 /*是否为素数*/ 
 8 int Is_Prime(int n)
 9 {
10     int ret = 1;
11     int i;
12     for(i=2;i<=sqrt(n);i++)
13     {
14         if(n%i == 0)
15         {
16             ret = 0;
17             break;
18         }
19     }
20     return ret;
21 }
22 
23 void func(int n)
24 {
25     int num = a[0];
26     int index = 1,count = 0;
27     for(num;num < n;)
28     {
29         num += 2;
30         if(Is_Prime(num))
31         {
32             a[index] = num;
33             if(a[index]-a[index-1] == 2)
34                 count++;
35             index++;
36         }
37         
38     }
39     
40     printf("%d",count);
41 }
42 
43 int main()
44 {
45     int n;
46     scanf("%d",&n);
47     a[0]=3; 
48     func(n);
49 }