#include <stdio.h>
main()
{int a[101],b[101];
int i,p,count;
for(i=1;i<=100;i++)
{a[i]=i;b[i]=1;}
i=1;count=100;
while(count!=1)
{ p=0;
while(b[i]==1)
{p++;
if(p==3)
{
b[i]=0;
p=0;
count--;
}
i++;
if(i==101) i=1;
}
}
for(i=1;i<=100;i++)
if(b[i]==1) printf("%d",i);
}