#include<stdio.h> #include<mat

#include<stdio.h>
#include<math.h>
int judgeprime(int n);
int main( )
{
int m,j,k;
int count=1;
printf("%4d=%4d+%4d ",4,2,2);
for (m=6;m<=2000;m=m+2)
{
k=m/2;
for(j=3;j<=k;j=j+2)
if(judgeprime(j)&&judgeprime(m-j))
{
printf("%4d=%4d+%4d ",m,j,m-j);
count++;
if(count%4==0)
printf("\n");
break;
}
}
printf("\n");
return 0;
}
int judgeprime(int n)
{
int i,k;
if(n==1)
return 0;
k=(int)sqrt(n);
for(i=2;i<=k;i++)
if(n%i==0)
return 0;
return 1;
}