#include<iostream>
#include<string>
#include<string.h>
#include<algorithm>
#include<stdio.h>
#include<cmath>
#include<vector>
#include<utility>
#include<stack>
#include<queue>
#include<list>
#include<bitset>
#include<functional>

#define FOR(i, a, b) for(int i=(a);i<=(b);i++)
#define RFOR(i, a, b) for(int i=(a);i>=(b);i--)
#define MOD 1000000007
#define INF 1000000000

using namespace std;


int main(void) {
	int p1, p2;
	int n;
	int r;
	int dp[1000];
	int count = 0;

	cin >> p1 >> p2 >> n;
	FOR(i, 1, n) {
		cin >> r;
		dp[r]++;
	}
	FOR(i, 1, 999) {
		if (dp[i] >= 2) {
			count += (dp[i] - 1)*(p1 + p2);
		}
	}

	cout << count << endl;
	return 0;
}