1389E - Calendar Ambiguity - CodeForces Solution

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;

typedef pair<int,int> ii;
typedef pair<ll,ll> pll;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<ll> vll;
typedef vector<pll> vpll;

#define PB push_back
#define PF push_front
#define PPB pop_back
#define PPF pop_front
#define X first
#define Y second
#define MP make_pair
#define all(x) (x).begin(), (x).end()

const int mod = 1e9 + 7; //998244353;
const int inf = 1e9 + 7;
const ll INF = 1e18 + 7;
const int logo = 20;
const int MAXN = 1e6 + 7;
const int off = 1 << logo;
const int trsz = off << 1;
const int dx[] = {1, -1, 0, 0};
const int dy[] = {0, 0, -1, 1};



void solve(){
	int m, d, w;
	cin >> m >> d >> w;
	ll need = w / __gcd(w, d - 1), bg = min(m, d);
	ll njv = bg / need;
	cout << (ll)bg * (ll)njv - need * (ll)njv * (ll)(njv + 1) / (ll)2 << "\n";
}

int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cout.tie(NULL);
	int tt = 1;
	cin >> tt;
	while(tt--) solve();
	return 0;
}