#include<stdio.h> int n; int a[9999],b[9999],t,ans; int main() { scanf("%d",&n); a[1]=1; for(int i=2;i<=n;i++) if(a[i]==0) for(int j=2;j*i<=n;j++) a[i*j]=1; for(int i=2;i<=n;i++) if(a[i]==0) b[++t]=i; for(int i=1;i<=t;i++) for(int j=i;j<=t&&n-b[i]-b[j]>=2;j++) if(a[n-b[i]-b[j]]==0&&b[i]<=b[j]&&b[j]<=n-b[i]-b[j]) ans++; printf("%d\n",ans); for(int i=1;i<=t;i++) for(int j=i;j<=t&&n-b[i]-b[j]>=2;j++) if(a[n-b[i]-b[j]]==0&&b[i]<=b[j]&&b[j]<=n-b[i]-b[j]) printf("%d=%d+%d+%d\n",n,b[i],b[j],n-b[i]-b[j]); return 0; } /************************************************************** Problem: 1273 User: admin Language: C Result: Accepted Time:9 ms Memory:1224 kb ****************************************************************/