Stack based Flood Fill algorithm in Python

tommy.py

row=int(input())
col=int(input())
xpoint=int(input())
ypoint=int(input())
mult = row * col 
p=[]

def isPrime(num):
    for x in reversed(range(2,num)):
        if num%x==0 and num>1 :
            return 1
    return 0

for x in range(mult):
    p.append(isPrime(x))
	
width=col
height=row
def getpixel(row,col):
    return p[row*width+col]
	
def printArray():	
    for rowx in range(height):
        for coly in range(width):
            print(getpixel(rowx,coly),end=" ")
        print()
	


	
def number(row,col):
    return row*width+col
	
z=[]

def tomfilleralgo(row,col,color,inputcolor):
    x=getpixel(row,col)
    if x==color:
        print("Hi")
        p[number(row,col)]=inputcolor
        if (row>0):
            f1=[row-1,col]
            if not f1 in z:
                z.append(f1)
                tomfilleralgo(f1[0],f1[1],color,inputcolor)
        if (row<height-1):
            f2=[row+1,col]
            if not f2 in z:
                z.append(f2)
                tomfilleralgo(f2[0],f2[1],color,inputcolor)
        if (col<width-1):
            f3=[row,col+1]
            if not f3 in z:
                z.append(f3)
                tomfilleralgo(f3[0],f3[1],color,inputcolor)
        if (col>0):
            f4=[row,col-1]
            if not f4 in z:
                z.append(f4)
                tomfilleralgo(f4[0],f4[1],color,inputcolor)

printArray()
print()				
tomfilleralgo(xpoint,ypoint,getpixel(xpoint,ypoint),2)
z=[]
print(z)
printArray()


'''
need to keep a handy pixel pool
need to keep a array  for drawd checking CGPoint
need a function that continously edits the array and keeps a lock
need a function to write the modified buffer to the UIImage

'''