code: def count_paths(m, n):
      if m < 1 or n < 1:
          return -1
      count = [[None for j in range(n)] for i in range(m)]
  
      # Taking care of the edge cases- matrix of size 1xn or mx1
      for i in range(n):
          count[0][i] = 1
      for j in range(m):
          count[j][0] = 1
  
      for i in range(1, m):
          for j in range(1, n):
              # Number of ways to reach a[i][j] = number of ways to reach
              #                                   a[i-1][j] + a[i][j-1]
              count[i][j] = count[i - 1][j] + count[i][j - 1]
  
      print(count[m - 1][n - 1])
  
label_desc: Use image node_id 1 for calling a global function with example usage: count_paths(m, n) and returns: unknown