Python: Function that takes a positive integer and returns the sum of the cube of all the positive integers smaller than the specified number

Python Basic: Exercise-149 with Solution

Write a Python function that takes a positive integer and returns the sum of the cube of all the positive integers smaller than the specified number.

Ex.: 8 = 7³+6³+5³+4³+3³+2³+1³ = 784

Sample Solution-1:

Python Code:

def sum_of_cubes(n):
 n -= 1
 total = 0
 while n > 0:
   total += n * n * n
   n -= 1
 return total
print("Sum of cubes smaller than the specified number: ",sum_of_cubes(3))

Sample Output:

Sum of cubes smaller than the specified number:  9

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Sample Solution-2:

Python Code:

def sum_of_cubes(n):
   if n < 0:
       raise ValueError('n must be positive number!')
   return n*n*(n*n-2*n+1)/4
print("Sum of cubes smaller than the specified number: ",sum_of_cubes(3))
print("Sum of cubes smaller than the specified number: ",sum_of_cubes(6))

Sample Output:

Sum of cubes smaller than the specified number:  9.0
Sum of cubes smaller than the specified number:  225.0

Flowchart:

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The following tool visualize what the computer is doing step-by-step as it executes the said program:

Sample Solution-3:

Python Code:

def sum_of_cubes(n):
   result = 0
   if n > 0:
       for i in range(n):
           result += i * i * i
       return result
   elif n <= 0:
       raise ValueError('n must be positive number!')
print("Sum of cubes smaller than the specified number: ",sum_of_cubes(3))
print("Sum of cubes smaller than the specified number: ",sum_of_cubes(6))

Sample Output:

Sum of cubes smaller than the specified number:  9
Sum of cubes smaller than the specified number:  225

Flowchart:

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Python Code Editor :

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