#include<iostream> // cin\cout\endl #include<cstdio> //scanf()\printf() #include<cstring> // strcpy()\strcat()\strcmp()\strlen()\memset() #include<cmath> //sqrt()\pow()\abs()\ceil()\floor()\max()\min() using namespace std; int a(int x) { if(x==10)return 1; return (a(x+1)+1)*2; } int main(){ cout<<a(1)<<endl; return 0; }