HDU 2520 I am a rookie I am afraid

2019-05-27

17:52:01

Come on! ! !

We should carefully look at the question time, it is easy to forget the last 10 000%

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int t, n;
    // cin >> t >> n;
    scanf("%d", &t);
    while (t--)
    {
        // cin >> n;
        scanf("%d", &n);
        long long sum = 0;
        for (int i = 1,j = 1;i <= n; i++, j += 2)
        {
            sum += j;
            sum %= 10000;
        }
        cout << sum << endl;
    }
    return 0;
}

 Another approach: use physical formula

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int n,t;
    int v0=1,v;
    int s;
    while(cin>>n)
    {
        while(n--)
        {
        cin>>t;
        v=v0+2*(t-1);
        s=((v+v0)*t/2)%10000;
        cout<<s<<endl;
        }
    }
    return 0;
}