#include<iostream> using namespace std; int main(){ int kun ; cin >> kun; int sum = kun; int kong = kun; while(true){ kun = kong / 3; sum += kun; kong = kong % 3 + kun; if(kong < 3){ break; } } if (kong == 2){ sum++; } cout << sum; }

#include<iostream> using namespace std; int main(){ int n,sum=0,k; cin>>n; k=n; while(k>=3){ if (k>=3){ sum+=k/3; k=k%3+k/3; if (k%3==2){ k+=1; } }else{ break; } }cout<<n+sum; return 0; }

#include<iostream> using namespace std; int main(){ int kun ; cin >> kun; int sum = kun; int kong = kun; while(true){ kun = kong / 3; sum += kun; kong = kong % 3 + kun; if(kong < 3){ break; } } if (kong == 2){ sum++; } cout << sum; }