#include <iostream> using namespace std; int calculateGold(int days) { int totalGold=0; int i=1; int curGold=1; int dayCount=0; while (dayCount<days) { int count=i<(days-dayCount)?i:(days-dayCount); for (int j=0;j<count;j++) { totalGold += curGold; dayCount++; } curGold++; i++; } return totalGold; } int main() { int days; cin>>days; int result=calculateGold(days); cout<<result<<endl; return 0; }