codeforces#P1598A. Computer Game
Computer Game
Description
Monocarp is playing a computer game. Now he wants to complete the first level of this game.
A level is a rectangular grid of $2$ rows and $n$ columns. Monocarp controls a character, which starts in cell $(1, 1)$ — at the intersection of the $1$-st row and the $1$-st column.
Monocarp's character can move from one cell to another in one step if the cells are adjacent by side and/or corner. Formally, it is possible to move from cell $(x_1, y_1)$ to cell $(x_2, y_2)$ in one step if $|x_1 - x_2| \le 1$ and $|y_1 - y_2| \le 1$. Obviously, it is prohibited to go outside the grid.
There are traps in some cells. If Monocarp's character finds himself in such a cell, he dies, and the game ends.
To complete a level, Monocarp's character should reach cell $(2, n)$ — at the intersection of row $2$ and column $n$.
Help Monocarp determine if it is possible to complete the level.
The first line contains a single integer $t$ ($1 \le t \le 100$) — the number of test cases. Then the test cases follow. Each test case consists of three lines.
The first line contains a single integer $n$ ($3 \le n \le 100$) — the number of columns.
The next two lines describe the level. The $i$-th of these lines describes the $i$-th line of the level — the line consists of the characters '0' and '1'. The character '0' corresponds to a safe cell, the character '1' corresponds to a trap cell.
Additional constraint on the input: cells $(1, 1)$ and $(2, n)$ are safe.
For each test case, output YES if it is possible to complete the level, and NO otherwise.
Input
The first line contains a single integer $t$ ($1 \le t \le 100$) — the number of test cases. Then the test cases follow. Each test case consists of three lines.
The first line contains a single integer $n$ ($3 \le n \le 100$) — the number of columns.
The next two lines describe the level. The $i$-th of these lines describes the $i$-th line of the level — the line consists of the characters '0' and '1'. The character '0' corresponds to a safe cell, the character '1' corresponds to a trap cell.
Additional constraint on the input: cells $(1, 1)$ and $(2, n)$ are safe.
Output
For each test case, output YES if it is possible to complete the level, and NO otherwise.
Samples
4
3
000
000
4
0011
1100
4
0111
1110
6
010101
101010
YES
YES
NO
YES
Note
Consider the example from the statement.
In the first test case, one of the possible paths is $(1, 1) \rightarrow (2, 2) \rightarrow (2, 3)$.
In the second test case, one of the possible paths is $(1, 1) \rightarrow (1, 2) \rightarrow (2, 3) \rightarrow (2, 4)$.
In the fourth test case, one of the possible paths is $(1, 1) \rightarrow (2, 2) \rightarrow (1, 3) \rightarrow (2, 4) \rightarrow (1, 5) \rightarrow (2, 6)$.