A9473 | Washer, Dryer, Folder

You have $k$ pieces of laundry, each of which you want to wash, dry and fold. You are at a laundromat that has $n_{1}$ washing machines, $n_{2}$ drying machines and $n_{3}$ folding machines. Each machine can process only one piece of laundry at a time. You can't dry a piece of laundry before it is washed, and you can't fold it before it is dried. Moreover, after a piece of laundry is washed, it needs to be immediately moved into a drying machine, and after it is dried, it needs to be immediately moved into a folding machine.

It takes $t_{1}$ minutes to wash one piece of laundry in a washing machine, $t_{2}$ minutes to dry it in a drying machine, and $t_{3}$ minutes to fold it in a folding machine. Find the smallest number of minutes that is enough to wash, dry and fold all the laundry you have.

The only line of the input contains seven integers: $k,n_{1},n_{2},n_{3},t_{1},t_{2},t_{3}$ $(1<=k<=10^{4}; 1<=n_{1},n_{2},n_{3},t_{1},t_{2},t_{3}<=1000)$ .

Print one integer — smallest number of minutes to do all your laundry.