A13320 | Contest for Robots

Polycarp is preparing the first programming contest for robots. There are $n$ problems in it, and a lot of robots are going to participate in it. Each robot solving the problem $i$ gets $p_i$ points, and the score of each robot in the competition is calculated as the sum of $p_i$ over all problems $i$ solved by it. For each problem, $p_i$ is an integer not less than $1$ .

Two corporations specializing in problem-solving robot manufacturing, "Robo-Coder Inc." and "BionicSolver Industries", are going to register two robots (one for each corporation) for participation as well. Polycarp knows the advantages and flaws of robots produced by these companies, so, for each problem, he knows precisely whether each robot will solve it during the competition. Knowing this, he can try predicting the results — or manipulating them.

For some reason (which absolutely cannot involve bribing), Polycarp wants the "Robo-Coder Inc." robot to outperform the "BionicSolver Industries" robot in the competition. Polycarp wants to set the values of $p_i$ in such a way that the "Robo-Coder Inc." robot gets strictly more points than the "BionicSolver Industries" robot. However, if the values of $p_i$ will be large, it may look very suspicious — so Polycarp wants to minimize the maximum value of $p_i$ over all problems. Can you help Polycarp to determine the minimum possible upper bound on the number of points given for solving the problems?

The first line contains one integer $n$ ( $1 \le n \le 100$ ) — the number of problems.

The second line contains $n$ integers $r_1$ , $r_2$ , ..., $r_n$ ( $0 \le r_i \le 1$ ). $r_i = 1$ means that the "Robo-Coder Inc." robot will solve the $i$ -th problem, $r_i = 0$ means that it won't solve the $i$ -th problem.

The third line contains $n$ integers $b_1$ , $b_2$ , ..., $b_n$ ( $0 \le b_i \le 1$ ). $b_i = 1$ means that the "BionicSolver Industries" robot will solve the $i$ -th problem, $b_i = 0$ means that it won't solve the $i$ -th problem.

If "Robo-Coder Inc." robot cannot outperform the "BionicSolver Industries" robot by any means, print one integer $-1$ .

Otherwise, print the minimum possible value of $\max \limits_{i = 1}^{n} p_i$ , if all values of $p_i$ are set in such a way that the "Robo-Coder Inc." robot gets strictly more points than the "BionicSolver Industries" robot.