feat: add function and prev class codes

Author: sahilbansal11

forLoopsAndPatterns/challenge3.py

@@ -0,0 +1,4 @@
+N = int(input())
+
+for i in range(N):
+    print('*', end='')

forLoopsAndPatterns/challenge4.py

@@ -0,0 +1,15 @@
+N = int(input())
+
+# loop within loop
+# nested loops
+for j in range(N):
+    for i in range(N):
+        print('*', end='')
+    # after printed one row
+    # we need to start a new line
+    print()
+
+
+
+
+

forLoopsAndPatterns/challenge5.py

@@ -0,0 +1,25 @@
+# Challenge 5:
+# Given N = 3 print
+"""
+* => 1 star
+** => 2 stars
+*** => 3 stars
+
+start = 1
+end = N + 1
+inc = 1
+
+range(1, N + 1)
+"""
+
+N = int(input())
+# how can I print numbers from 1 to N?
+
+for i in range(1, N + 1):
+    # print(i)
+    # how can I print i stars?
+    for j in range(i):
+        print('*', end='')
+    # after printing one row, we print a new line
+    print()
+

forLoopsAndPatterns5/break1.py

@@ -0,0 +1,16 @@
+# say we want to break at 50
+
+for i in range(100):
+    print(i, end=' ')
+    if i == 50:
+        break
+
+
+print()
+
+# we can also break the loop directly
+
+for i in range(100):
+    print(i)
+    break
+

forLoopsAndPatterns5/challenge1.py

@@ -0,0 +1,16 @@
+# print all integers from 1 to n
+
+n = int(input())
+
+# this does not print the value N=n
+for i in range(1, n):  # starting at 1, ending at n
+    print(i, end=' ')
+
+print()
+
+
+# this will print all values from 1 to n
+for i in range(1, n + 1):
+    # end = n + 1, because we want n to included
+    print(i, end=' ')
+

forLoopsAndPatterns5/challenge2.py

@@ -0,0 +1,14 @@
+# print all odd integers from 1 to n
+
+n = int(input())
+
+# prints all numbers from 1 to n
+for i in range(1, n + 1):
+    print(i, end=' ')
+
+print()
+
+# we can increment by 2 now
+for i in range(1, n + 1, 2):
+    print(i, end=' ')
+

forLoopsAndPatterns5/challenge3.py

@@ -0,0 +1,8 @@
+# print the number of factors of a number n
+
+n = int(input())
+
+for i in range(1, n + 1):
+    if n % i == 0:
+        print(i, end=' ')
+

forLoopsAndPatterns5/challenge4.py

@@ -0,0 +1,11 @@
+# print a^b
+
+a = int(input())
+b = int(input())
+
+ans = 1
+for i in range(b):  # range(1, b + 1) also works
+    ans *= a
+    print('ans now is: ', ans)
+
+print('final ans is: ', ans)

forLoopsAndPatterns5/continue1.py

@@ -0,0 +1,31 @@
+print(list(range(-1, 10, 2)))
+
+# what if we want to pick these values one by one
+# we can simply use a for loop to iterate one by one
+
+for i in range(-1, 10, 2):
+    print(i, end=' ')
+
+# now let us say we want to print their squares
+print()  # prints a new line
+
+for i in range(-1, 10, 2):
+    print(i * i, end=' ')
+
+
+# let's say we want to find the sum of these numbers
+
+sum = 0
+for i in range(-1, 10, 2):
+    sum += i
+
+print()
+print('sum of all these numbers', sum)
+
+print()
+print('Now using while loop')
+
+i = -1
+while i < 10:
+    print(i * i, end=' ')
+    i += 2

forLoopsAndPatterns5/forLoop1.py

@@ -0,0 +1,23 @@
+print(range(6))  # this is not helpful
+
+print(list(range(6)))  # converting this to a list
+# we will talk about list in the next classes
+
+print(list(range(2, 8)))
+# [2, 3, 4, 5, 6, 7]
+
+print(list(range(-1, 10, 2)))  # values < 10 are included
+# [-1, 1, 3, 5, 7, 9]
+
+print(list(range(10, 0, -2)))  # values > 0 are included
+# [10, 8, 6, 4, 2]
+
+print(list(range(10, 12, -2)))  # values > 12 are included
+# 10 itself is not greater than 12
+# does not include anything
+
+# []
+
+print(list(range(5, 1)))  # start = 5, end = 1, inc = 1
+# values < end, 5 itself is not less than end
+# []

forLoopsAndPatterns5/range1.py

@@ -0,0 +1,23 @@
+
+# default argument
+def my_range(end, start = 3):
+    print('start', start)
+    print('end', end)
+
+    while start < end:
+        print(start, end=' ')
+        start += 1
+
+# my_range(1, 10)
+
+my_range(10)  # default start = ?
+print()
+my_range(5)
+print()
+
+my_range(1, 10)
+
+print()
+
+my_range(start=1, end=10)
+# keyword arguments, more explained in next class

functions/customRange.py

@@ -0,0 +1,20 @@
+# WHY are we not allowed to keep default arguments in
+# the starting
+
+# ALL THE DEFAULT ARGUMENTS SHOULD COME AT THE END
+
+def introduce(age = 22, name = 'Sahil'):
+    print('Hello, I am', name)
+    print('I am', age, 'years old')
+    print()
+
+introduce('Sahil')
+introduce(23)
+
+# Does not allow default arguments in the start
+"""
+def add(n1 = 2, n2):
+    return n1 + n2
+
+print(add(3, 5))
+"""

functions/defaultArgsFailing.py

@@ -0,0 +1,14 @@
+def introduce(name, age = 22):
+    print('Hello, I am', name)
+    print('I am', age, 'years old')
+    print()
+
+introduce('Sahil', 22)
+
+introduce('Kuldip', 25)
+
+introduce('Sahil')
+
+introduce('Rahul', 24)
+
+

functions/introduce.py

@@ -0,0 +1,5 @@
+t = int(input())
+
+for i in range(t):
+    x = int(input())
+    print(i, 'th input is:', x)

functions/multipleInputs.py

@@ -0,0 +1,23 @@
+# make my own function that prints some data
+
+def my_print_fun(val):
+    # we can use the library's print function
+    print(val)
+
+my_print_fun(5)
+my_print_fun("Hello world")
+my_print_fun(5.66)
+print()
+# write a function that adds 2 numbers
+
+def add_2_numbers(num_1, num_2):
+    print(num_1 + num_2)
+
+add_2_numbers(5, 7)
+add_2_numbers(5.7, 9.6)
+add_2_numbers(-1, -2)
+
+x = 1
+y = 2
+add_2_numbers(x, y)
+

functions/myPrintFunction.py

@@ -0,0 +1,5 @@
+def add_2_nums_with_return(n1, n2):
+    return n1 + n2
+
+y = add_2_nums_with_return(5, 6)
+print(y)

functions/noReturnCapture.py

@@ -0,0 +1,29 @@
+# make a tea, print the recipe
+# define a function
+
+# add_two_numbers
+
+# def function_name():
+#     # function code will start here
+
+def tea():
+    print('Light the stove')
+    print('Boil the water in a tea pan')
+    print('Add tea powder')
+    print('Add milk')
+    print('Add sugar')
+    print('Use a sieve and filter in a cup')
+    print()
+
+
+# call a function
+tea()
+
+tea()
+
+tea()
+
+# 0, 1, 2, ..., 9
+for i in range(10):
+    tea()
+

functions/recipe.py

@@ -0,0 +1,22 @@
+
+def add_2_nums(n1, n2):
+    print(n1 + n2)
+
+
+x = add_2_nums(1, 2)
+print(x)
+print()
+
+# try to return some value now
+
+def add_2_nums_with_return(n1, n2):
+    return n1 + n2
+
+y = add_2_nums_with_return(5, 6)
+print(y)
+
+if y % 2 == 0:
+    print('Result of addition is even')
+else:
+    print('Result of addition is odd')
+

functions/returnValues.py

@@ -0,0 +1,15 @@
+
+def add(x, y):
+    return x + y
+
+def square(x):
+    return x*x
+
+n1 = square(3)
+print('n1 is', n1)
+
+n2 = square(5)
+print('n2 is', n2)
+
+print(add(n1, square(9)))
+

functions/squareNum.py

@@ -0,0 +1,11 @@
+n = int(input())
+
+# loop over n times, say n = 5
+# r = 1, 2, 3, 4, 5
+for r in range(1, n + 1):
+    # loop over (n - r + 1) times
+    for c in range(n - r + 1):
+        print('*', end='')
+    print()
+
+

patternPrinting/downwardTriangle.py

@@ -0,0 +1,30 @@
+
+n = int(input())
+
+for r in range(1, n):
+
+    # print (n - r + 1) *s
+    for c in range(n - r + 1):
+        print('*', end='')
+
+    # print 2*(r - 1) spaces
+    for c in range(2*(r - 1)):
+        print(' ', end='')
+
+    # print (n - r + 1) *s
+    for c in range(n - r + 1):
+        print('*', end='')
+
+    print()
+
+# code for the HW (challenge 7)
+for r in range(1, n + 1):
+    for c in range(r):
+        print('*', end='')
+
+    for c in range(2*(n - r)):
+        print(' ', end='')
+
+    for c in range(r):
+        print('*', end='')
+    print()