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| ≤ 1 and |y_1 - y_2| ≤ 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.
  
  Input
  
  The first line contains a single integer t (1 ≤ t ≤ 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 ≤ n ≤ 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.
  
  Example
  
  Input
  
  
  4
  3
  000
  000
  4
  0011
  1100
  4
  0111
  1110
  6
  010101
  101010
  
  
  Output
  
  
  YES
  YES
  NO
  YES
  
  Note
  
  Consider the example from the statement.
  
  In the first test case, one of the possible paths is (1, 1) → (2, 2) → (2, 3).
  
  In the second test case, one of the possible paths is (1, 1) → (1, 2) → (2, 3) → (2, 4).
  
  In the fourth test case, one of the possible paths is (1, 1) → (2, 2) → (1, 3) → (2, 4) → (1, 5) → (2, 6).
solution: def game(n):
      n=n-1;
      mtx = []
      a = str(input())
      mtx.append(a);
      b=str(input())
      mtx.append(b);
  
      stk = []
      stk.append([0, 0]);
  
      visit = [[], []]
      for i in range(2):
          for j in range(n+1):
              visit[i].append(False)
  
      visit[0][0]==True
  
      while (len(stk)!=0):
          x = stk.pop()
          
          if (x[0]>1 or x[0]<0 or x[1]>n or x[1]<0):
              continue;
  
          if (x[0]==0):
              if (mtx[0][x[1]]=="0"):
                  if (visit[1][x[1]]==False):
                      stk.append([1, x[1]])
                      visit[1][x[1]] = True;
          if (x[0]==1):
              if (mtx[1][x[1]]=="0"):
                  if (visit[0][x[1]]==False):
                      stk.append([0, x[1]])
                      visit[0][x[1]] = True;
          
          if (x[1]<n):
              if (mtx[x[0]][x[1]+1]=="0"):
                  if (visit[x[0]][x[1]+1]==False):
                      stk.append([x[0], x[1]+1])
                      visit[x[0]][x[1]+1] = True;
          
          if (x[1]>0):
              if (mtx[x[0]][x[1]-1]=="0"):
                  if (visit[x[0]][x[1]-1]==False):
                      stk.append([x[0], x[1]-1])
                      visit[x[0]][x[1]-1] = True;
  
      return visit[1][n];
  
  for _ in range(int(input())):
      flg = game(int(input()))
  
      if flg:
          print("YES")
      else:
          print("NO")
          
  
  
  