// yukicoder: No.586 ダブルブッキング
// 2019.4.19 bal4u

#include <stdio.h>

#if 1
#define gc() getchar_unlocked()
#else
#define gc() getchar()
#endif
int in()    // 非負整数の入力
{
	int n = 0, c = gc();
	do n = 10 * n + (c & 0xf), c = gc(); while (c >= '0');
	return n;
}

int f[1000];

int main()
{
	int i, N, P, cnt;

	P = in() + in();
	N = in(); while (N--) f[in()]++;
	cnt = 0; for (i = 1; i <= 999; i++) if (f[i]) cnt += f[i]-1;
	printf("%lld\n", (long long)P * cnt);
	return 0;
}