7: Lists and Mutability, Dictionaries, Introduction to Efficiency

import math

#Get base
inputOK = False
while not inputOK:
    base = input(‘Enter base: ‘)
    if type(base) == type(1.0) : inputOK = True
    else: print(‘Error. Base must be floating point number.’)

#Get Height
inputOK = False
while not inputOK:
    height = input(‘Enter height: ‘)
    if type(height) == type(1.0) : inputOK = True
    else: print(‘Error. Height must be floating point number.’)

hyp = math.sqrt (base * base + height * height)

print ‘Base: ‘ + str(base) + ‘, height: ‘ + str(height) + ‘, hyp: ‘ + str(hyp)

def getFloat(requestMsg, errorMsg):
    inputOK = False
    while not inputOK:
        val = input(requestMsg)
        if type(val) == type(1.0) : inputOK = True
        else: print(errorMsg)
    return val

base = getFloat(‘Enter base: ‘, ‘Error: base must be a float’)
height = getFloat(‘Enter height:’, ‘Error height must be a float’)

hyp = math.sqrt(base * base + height * height)

print ‘Base: ‘ + str(base) + ‘, height: ‘ + str(height) + ‘, hyp: ‘ + str(hyp)

def exp1(a, b):
    ans = 1
    while (b > 0):
        ans *= a
        b -= 1
    return ans

def exp2(a, b):
    if b == 1:
        return a
    else:
        return a * exp2(a, b – 1)

def exp3(a, b):
    if b == 1:
        return a
    if (b % 2) == b:
        return exp3(a * a, b / 2)
    else:
        return a * exp3(a, b – 1)

def g(n):
    x = 0
    for i in range(n):
        for j in range(n):
            x += 1
    return x
def Towers(size, fromStack, toStack, spareStack):
    if size == 1:
        print ‘Move disk from ‘, fromStack, ‘to ‘, toStack
    else:
        Towers(size – 1, fromStack, spareStack, toStack)
        Towers(1, FromStack, toStack, spareStack)
        Towers(size – 1, spareStack, toStack, fromStack)