Chapter 3: The Loop Control Structure

Simple Interest using While Loop, Page number: 99

In [1]:
#Variable declaration
count = 1
pr = [1000,2000,3500]
yr = [5,5,5]
intr = [13.5,13.5,3.5]

# while loop
while count <= 3:
    #Input from the user
    #p,n,r = raw_input("Enter values of p, n and r : ").split()
    p = pr[count-1] # principle
    n = yr[count-1] # number of years
    r = intr[count-1]# rate of interest

    #Calculation
    si = p * n * r / 100 ; #formula for simple interest

    #Result
    print "Simple interest = Rs.",si 

    #Increment count
    count = count + 1
    

Simple interest = Rs. 675.0
Simple interest = Rs. 1350.0
Simple interest = Rs. 612.5

Simple Interest using For Loop , Page number: 109

In [2]:
pr = [1000,2000,3500]
yr = [5,5,5]
intr = [13.5,13.5,3.5]

#for loop
for count in range(1, 4):
    #Input from the user
    #p,n,r = raw_input("Enter values of p, n and r : ").split()
    p = pr[count-1] # principle
    n = yr[count-1] # number of years
    r = intr[count-1]# rate of interest
    
    #Calculation
    si = p * n * r / 100 ; #formula for simple interest

    #Result
    print "Simple interest = Rs.",si 

Simple interest = Rs. 675.0
Simple interest = Rs. 1350.0
Simple interest = Rs. 612.5

Nested For Loops , Page number: 114

In [3]:
#nested for loops
for r in range(1,4): #outer loop
    for c in range(1,3): #inner loop
        s = r + c #find the sum
        print "r = %d c = %d sum = %d" % (r, c, s) #Display result
    

r = 1 c = 1 sum = 2
r = 1 c = 2 sum = 3
r = 2 c = 1 sum = 3
r = 2 c = 2 sum = 4
r = 3 c = 1 sum = 4
r = 3 c = 2 sum = 5

Do While Loop , Page number: 116

In [5]:
#do while loop
while True:
    #num = raw_input("Enter a number: ")
    num = 11
    print "square of %d is %d"%(num, num * num )
    print "Want to enter another number y/n: " 
    another = 'n'
    print another
    if another == 'y':
        continue
    else:
        break
    

square of 11 is 121
Want to enter another number y/n: 
n

Do While using For Loop, Page number: 117

In [7]:
#Variable declaration
another = 'y'

#do while loop
import sys
for i in range(1,10000): #infinte loop
    #num = raw_input("Enter a number: ")
    num = 11
    print "square of %d is %d"%(num, num * num )
    print "Want to enter another number y/n: " 
    another = 'n'
    print another
    if another == 'y':
        continue
    else:
        break
    

square of 11 is 121
Want to enter another number y/n: 
n

Do While using While Loop, Page number: 117

In [8]:
#Variable declaration
another = 'y'

#do while loop
while another == 'y':
    #num = raw_input("Enter a number: ")
    num = 11
    print "square of %d is %d"%(num, num * num )
    print "Want to enter another number y/n: " 
    another = 'n'
    print another
   
    

square of 11 is 121
Want to enter another number y/n: 
n

Prime Number, Page number: 118

In [9]:
#Input from user
#num = raw_input("Enter a number: ")
num = 11

#Variable declaration
i = 2

#while loop
while i <=(num - 1):
    if num % i == 0:
        print "Not a prime number"  #Display if not prime number
        break
    i += 1

#Display if prime number
if i == num:
    print  "Prime number" 

Prime number

Break Statement , Page number: 119

In [11]:
#Variable declaration
i = 1
j = 1

#while loops
while i <= 100 : #outer loop
    i = i+1
    while j <= 200 : #inner loop
        j = j+1
        if j == 150:
            break #break statement in inner loop
        else:
            print i, j 
            

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Continue Statement , Page number: 120

In [12]:
#for loops
for i in range(1,3):
    for j in range(1,3):
        if i==j :
            continue # continue statement
        print  i , j
        

1 2
2 1
In [ ]: