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 co_solve(n, ar, br, as, bs, at, bt) {
	let r = 0n;
	for (let i = 0n, di = n; i < ar && di >= 0n; i += 1n, di -= as) {
		for (let j = 0n, dj = di; j < ar && dj >= 0n; j += 1n, dj -= at) {
			let t = (dj / ar) * br + i * bs + j * bt;
			r = (r < t) ? t : r;
		}
	}
	return r;
}

let r1 = co_solve(n, a0, b0, a1, b1, a2, b2);
let r2 = co_solve(n, a1, b1, a2, b2, a0, b0);
let r3 = co_solve(n, a2, b2, a0, b0, a1, b1);

let r = r1;
r = (r < r2) ? r2 : r;
r = (r < r3) ? r3 : r;

console.log(r.toString());