let l = require("fs").readFileSync("/dev/stdin", "utf8").trim().split("\n");
let n = BigInt(l[0]);
let [a0, b0] = l[1].split(" ").map(s => BigInt(s));
let [a1, b1] = l[2].split(" ").map(s => BigInt(s));
let [a2, b2] = l[3].split(" ").map(s => BigInt(s));

function solve(n, ap, bp, aq, bq, ar, br) {
	let r = 0n, imax = ap * bq, jmax = ap * br;
	for (let i = 0n, di = n; i < imax && di >= 0n; i += bq, di -= aq) {
		for (let j = 0n, dj = di; j < jmax && dj >= 0n; j += br, dj -= ar) {
			let t = dj / ap * bp + i + j;
			r = (r < t) ? t : r;
		}
	}
	return r;
}

let r1 = solve(n, a0, b0, a1, b1, a2, b2);
let r2 = solve(n, a1, b1, a2, b2, a0, b0);
let r3 = solve(n, a2, b2, a0, b0, a1, b1);
let r = (r1 > r2 && r1 > r3) ? r1 : (r2 > r3) ? r2 : r3;
console.log(r.toString());