第三章 41题

<span style="font-size:18px;">#include<stdio.h>
#include<math.h>
int prim(int num)
{
int i,j=0;
for(i=2;i<=sqrt(num);i++)
{
if(num%i==0)
j++;
}
if(j==0)
return 1;
else
return 0;
}
int main()
{
int a,k;
printf("请输入一个大于2的偶数:");
scanf("%d",&a);

for(k=2;k<=a/2;k++)
{
if(prim(k)&&prim(a-k))

printf("%d=%d+%d\n",a,k,a-k); }

return 0;
}</span>

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