Answer to Question #299849 in Python for Paul

Question

Start with an infinite two dimensional grid filled with zeros, indexed from (1,1) at the bottom left corner with coordinates increasing toward the top and right. Given a series of coordinates (r, c), where ris the ending row and cis the ending column, add 1 to each element in the range from (1,1) to (r, C) inclusive. Once all coordinates are processed, determine how many cells contain the maximal value in the grid. Example upRight = ["14", "23", "4 1"] The two space-separated integers within each string represent rand c respectively. The following diagrams show each iteration starting at zero. The maximal value in the grid is 3, and there is 1 occurrence at cell (1, 1). Initial Grid 40 0 0 0 30 0 0 0 20 0 0 0 1 0 0 0 0 1 2 3 4 Step 0:r=1, c = 4 Step 1: r = 2, c = 3 Step 2:r =4,c= 1 4000 0 4 0 0 0 0 4 100 0 30 000 3000 0 3 1000 2 0 0 0 0 2 1 1 1 0 2 2 1 0 1 1 1 1 1 1 2 2 2 1 1 3 2 2 1 1 2 3 4 1 2 3 4 1 2 3 4

Answer 1

row = 5
col = 5
def isPath(arr):
    Dir = [[0, 1], [0, -1], [1, 0], [-1, 0]]
    q = []
    q.append((0, 0))
    while (len(q) > 0):
        p = q[0]
        q.pop(0)
        arr[p[0]][p[1]] = -1
        if (p == (row - 1, col - 1)):
            return True
        for i in range(4):
            a = p[0] + Dir[i][0]
            b = p[1] + Dir[i][1]
            if (a >= 0 and b >= 0 and a < row and b < col and arr[a][b] != -1):
                q.append((a, b))
    return False

arr = [[0, 0, 0, -1, 0],
       [-1, 0, 0, -1, -1],
       [0, 0, 0, -1, 0],
       [-1, 0, -1, 0, -1],
       [0, 0, -1, 0, 0]]
if (isPath(arr)):
    print("Yes")
else:
    print("No")