Sum

/* Murad Eynizade */

#include <bits/stdc++.h>
#define intt long long
#define FAST_READ ios_base::sync_with_stdio(0);cin.tie(0);
#define SIZE 1000001
#define INF INT_MAX
#define F first
#define S second
#define in(a) scanf("%d",&a);
#define outn(a) printf("%d\n",&a);
#define outs(a) printf("%d ",&a);


using namespace std;

intt ans = 0;

set< pair<int , pair<int,int> > >st;

int main()
{
    FAST_READ;
    int n;
    cin>>n;
    for (int i = 1;i <= n - 2;i++) {
        for (int j = i;j <= n - 1;j++) {
           vector<int>v(3);
           v[0] = i;
           v[1] = j;
           v[2] = n - (i + j);
           if (v[2] <= 0)continue;
           if (v[0] == v[1] || v[1] == v[2] || v[0] == v[2])continue;
           sort(v.begin(),v.end());
           st.insert({v[0] , {v[1] , v[2]}});
        }
    }
    cout<<st.size()<<endl;
    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED

Test 20

Verdict: ACCEPTED

Test 21

Verdict: ACCEPTED

Test 22

Verdict: ACCEPTED

Test 23

Verdict: ACCEPTED

Test 24

Verdict: ACCEPTED

Test 25

Verdict: ACCEPTED

Test 26

Verdict: ACCEPTED

Test 27

Verdict: ACCEPTED

Test 28

Verdict: ACCEPTED