Submission

Score: 100

User: I_am_me

Problemset: โชว์ของโลมา

Language: cpp

Time: 0.003 second

Submitted On: 2026-01-03 18:14:33

#include <bits/stdc++.h>
using namespace std ;
int main() {
    int n ;
    cin>>n ;
    vector<long long> lastline(n) ;
    lastline[0] = 1+3*(n-1) ;
    if (n%2 == 1) {
        for(int i = 1;i<n-1;i++) {
            if (i%2==1) lastline[i] = lastline[i-1]+1 ;
            if (i%2==0) lastline[i] = lastline[i-1]+4*(n-i)-3 ;
        }
        lastline[n-1] = lastline[n-2] +1 ;
    }
    if (n%2==0) {
        for(int i = 1;i<n-1;i++) {
            if (i%2==1) lastline[i] = lastline[i-1]+1 ;
            if (i%2==0) lastline[i] = lastline[i-1]+5+8*(n/2-(i-(i-2)/2)) ;
        }
        lastline[n-1] = lastline[n-2] -1 ;
    }
    long long sum = 0;
    for(int i = 0;i<n;i++) {
        sum+=lastline[i]%10 ;
    }
    cout<<sum ;
}