4. Median of Two Sorted Arrays(Leetcode) Accepted solution

class Solution:

def findMedianSortedArrays(self,l1,l2):

sorted_new_list = l1 + l2

sorted_new_list.sort()

val = len(sorted_new_list)

if (val % 2 != 0):

return float(sorted_new_list[val //2])

else:

num1 = sorted_new_list[val//2 -1]

num2 = sorted_new_list [val//2]

return (num1 +num2 )/2

a = Solution()

print(a.findMedianSortedArrays([1,2,3,4,5] ,[6,7,8,9]))

leetcode problem2 (brute force) not all test cases passed

class Solution:
  def lengthOfLongestSubstring(self, s):
    if len(s) == 0:
      return 1
    else:
        self.l = ''
        self.count = 0
        self.mlist = []
        length =0
        for i in s:
            if i not in self.l:
                self.l += i
                self.count +=1
            elif i in self.l:
                self.mlist.append(self.count)
                self.count =0
                self.l = ''
                self.l +=i
                self.count +=1
            #return max(self.mlist)
            for i in self.mlist:
                if i > length:
                    length = i
            return length

a = Solution()
print(a.lengthOfLongestSubstring(""))

Leetcode problem1 brute force

class Solution:

def twoSum(self,nums, target):

thisdict = {}

#new_list = []

for i in range(0,len(nums)):

thisdict[nums[i]] = i

for i in thisdict:

rem = target - i

if rem in thisdict and rem != i:

return[thisdict[i],thisdict[rem] ]

a = Solution()

print(a.twoSum([3,3],6)) # It doesn't satisfy this use case

Data science class statisctisc

''def mean(x):

sum = 0

avg = 0

try:

for i in x:

sum+= i

avg = sum /len(x)

print(avg)

except ZeroDivisionError:

print("Division by zero error")

mean([])'''

import math

def mean(x):

return sum(x)/len(x) if len(x) is not 0 else 0

print(mean([1,2,3,5]))

def de_mean(x_list):

return abs(x_list[i]-mean(x_list[i]) for i in range(len(x_list)

print(de_mean([1,2,3,4,5]))

Python Data visualization, (Applied Data Science Class)

#sample code for plotting a bar diagram

import matplotlib.pyplot as plt

movies = ["Annie Hall", "Ben-Hur", "Casablanca", "Gandhi", "West Side Story"]

num_oscars = [5,11,3, 8, 10]

xs = [i + 0.1 for i, _ in enumerate(movies)]

plt.bar(xs, num_oscars)

plt.ylabel("# of Academy Awards")

plt.title("My favorite movies")

plt.xticks([i + 0.5 for i, _ in enumerate(movies)], movies)

plt.show()

#Create a Histogram of 1000 random grades

from collections import Counter

import matplotlin

matplotlib.use("Agg")

import matplotlib

grades =[]

#create a list of 1000 random grades between 0 and 100

decile = lamda grade:grade // 10 *10

histogram = COunter(decile(grade) for grade in grades)

plt.bar([x-4 for x n histogram.keys()], histogram.values(), 8)

plt.axis([-5, 105, 0, 5])

plt.xticks([10 * i for i in range(11)])

plt.xlabel("Decile")

plt.ylabel("# of Students")

plt.title("Distribution of the grades")

plt.savefig("histogram.png")