Submission

Score: 60

User: PeachyNHM

Problemset: โชว์ของโลมา

Language: cpp

Time: 0.002 second

Submitted On: 2026-03-06 10:45:37

// Online C++ compiler to run C++ program online
#include <bits/stdc++.h>
using namespace std;
int main() {
    int n;
    cin >> n;
    if(n==1){
        cout << 1;
        return 0;
    }
    else if(n==2){
        cout << 7;
        return 0;
    }
    else if(n==3){
        cout << 24;
        return 0;
    }
    
    int sum=0;
    int a=n*2+n-2;
    int plus=2+(4*(n-3));
 
    for(int i=1;i<=n/2;i++){
        if(i==1){
            sum+=(a%10)+((a+1)%10);
        }
        else if(i==n/2){
            a+=plus;
            if(n%2==0){
                sum+=(a%10)+((a-1)%10);
            }
            else{
                sum+=(a%10)+((a+1)%10)+((a+2)%10);
            }
        }
        else{
            a+=plus;
            sum+=(a%10)+((a+1)%10);
            plus-=8;
        }
    }
    cout << sum;
}