Question

Using recursion, write a program that asks a user to enter the starting coordinates (row, then column), the ending coordinates (row then column), and calculates the number of paths from the starting coordinate to the ending coordinate.

Answer 1

Answer:

The program in Python is as follows

def Paths(row,col):

if row ==0 or col==0:

 return 1

return (Paths(row-1, col) + Paths(row, col-1))

row = int(input("Row: "))

col = int(input("Column: "))

print("Paths: ", Paths(row,col))

Explanation:

This defines the function

def Paths(row,col):

If row or column is 0, the function returns 1

if row ==0 or col==0:

 return 1

This calls the function recursively, as long as row and col are greater than 1

return (Paths(row-1, col) + Paths(row, col-1))

The main begins here

This prompts the user for rows

row = int(input("Row: "))

This prompts the user for columns

col = int(input("Column: "))

This calls the Paths function and prints the number of paths

print("Paths: ", Paths(row,col))