#include <bits/stdc++.h>
#define ll long long
#define rep(i, n) for(int i=1;i<=n;i++)
using namespace std;
ll N, L, C;
int v[100005], qu[100005], ans, t;
int main() {
	freopen("running.in", "r", stdin);
	freopen("running.out", "w", stdout);
	cin >> N >> L >> C;
	rep(i, N) {
		cin >> v[i];
	}
	while(1) {
		rep(i, N) {
			v[i] *= 2;
			if(v[i] >= C) v[i] %= C, qu[i] ++;
		}
		t ++;
		rep(j, N) {
			rep(k, N) {
				if(v[j] > v[k] and qu[j] > qu[k]) {
					//cout<< j << " " << k << " " << t;
					ans ++;
					//cout<<"\n";
				}
			}
		}

		rep(t1, N) {
			if(qu[t1] >= L) 
			{
				goto aaa;
			}
		}
	}
aaa:
	cout << ans  - 1;
}