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

string ts,te;
int n,w;
int v[10005],m[10005];
int f[1005];

int main()
{
	cin>>ts>>te>>n;
	
	int s = 0,e = 0;
	if(ts[1] == ':')
		s = (ts[0] - '0') * 60 + (ts[2] - '0') * 10 + ts[3] - '0';
	else s = ((ts[0] - '0') * 10 + ts[1] - '0') * 60 + (ts[3] - '0') * 10 + ts[4] - '0';
	if(te[1] == ':')
		e = (te[0] - '0') * 60 + (te[2] - '0') * 10 + te[3] - '0';
	else e = ((te[0] - '0') * 10 + te[1] - '0') * 60 + (te[3] - '0') * 10 + te[4] - '0';
	w = e - s;
	
	int cnt = 0;
	for(int i = 1;i <= n;i ++)
	{
		int a,b,c;
		cin>>a>>b>>c;
		
		if(!c)c = 1005;
		
		for(int k = 1;k <= c;k *= 2)
		{
			m[++cnt] = a * k;
			v[cnt] = b * k;
			
			c -= k;
		}
		if(c)
		{
			m[++cnt] = a * c;
			v[cnt] = b * c;
		}
	}

	for(int i = 1;i <= cnt;i ++)
		for(int j = w;j >= m[i];j --)
			f[j] = max(f[j],f[j - m[i]] + v[i]);
	
	cout<<f[w]<<'\n';
	
	return 0;
}