NINJA

The $Ninja$ is disciplined and hardworking. Today, he wants to improve his $climbing$ skills. Let each level of two buildings be denoted by arrays $A$ and $B$ each with size $N$ and $A[i]$ or $B[i]$ denotes the $maximum$ height up to which he can jump if he was on that level of that particular array. He wants to reach on the $top$ of either of the two $adjacent$ walls of $same$ height. Here top