#include<stdio.h>
//#include<math.h>
long int d,prim,i,j,l,a[51],b[51]k,x[500],k1,cont;
int main()
{x[1]=2;1=1;
d=3;
do{prim=1;
for(i=1;(x[i]*x[i])<=d;i++)
if(d%x[i]==0){prim=0;break;}
if(prim){l++;x[l]=d;}
d=d+2;}
while(d<=997);
file*f
f=fopen("prim.in","r");
fscanf(f,"%ld",&kl);
fclose(f);
cont=168;
if(kl<168) k=x[k1+1};
else
{d=1001;
while(cont<=k1)
{prim=1;
for(i=1;x[i]*x[i]<=d;i++)
if(d%x{i}==0){prim=0;break;}
if(prim){cont++;k=d;}
d=d+2;
}
}
for(i=0;i<=50;i++)
{a[i]=k%10;k=k/10;}for(i=0;i<=15;i++)
for(j=0;j<=15;j++)
b[i+j]+=a[i]*a[j];
for(i=0;i<=30;i++)
{b[i+1]=b[i+1]+b[i]/10;b[i]=b[i]%10;}
while(b[i]==o)i--;
f=fopen("prim.out","w");
for(j=i;j>=0;j--)
fprintf(f,"%ld",b[j]);
fprintf(f,"\n");
fclosef(f)
return0;
}