Submission

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Score: 20

User: lolipop

Problemset: โชว์ของโลมา

Language: cpp

Time: 0.002 second

Submitted On: 2025-03-22 15:14:14

#include <iostream>

using namespace std;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    int sum = 0;
    sum = (3*n-2)%10+(3*n-1)%10;
    int num = 3*n-1;
    for(int i = 3;i <= n-3;i+=2)
    {
        num += ((4*n)-(4*i)+1);
        sum += (num)%10+(num+1)%10;
        num+=1; 
    }
    sum += (2*(n*n)-1)%10;
    cout << sum;
}