#include <stdio.h>
#include <algorithm>
using namespace std;
#define MM 10
#define MK 30

int N, M, K;
int a[MK], b[MK], c[MK];
int rst, tmp;

int s[MM];
void DFS(int i)
{
	if (i == K)
	{
		rst = max(rst, tmp);
		return;
	}
	bool flag = true;
	for (int j = a[i]; j <= b[i]-1; j++)
	{
		if (s[j] + c[i] > N) flag = false;
	}

	if (flag)
	{
		for (int j = a[i]; j <= b[i] - 1; j++) s[j] += c[i];
		tmp += (b[i] - a[i])*c[i];
		DFS(i + 1);
		for (int j = a[i]; j <= b[i] - 1; j++) s[j] -= c[i];
		tmp -= (b[i] - a[i])*c[i];
	}

	DFS(i + 1);
}

int main(void)
{
	while (scanf("%d%d%d", &N, &M, &K))
	{
		if (N == 0 && M == 0 && K == 0) return 0;

		for (int i = 0; i < K; i++) scanf("%d%d%d", &a[i], &b[i], &c[i]);

		rst = 0;
		DFS(0);
		printf("%d\n", rst);
	}

	return 0;
}