Day-28 Dictionary, Frequency of character using nested loops

Dictionary-{}

Dictionaries are used to store data values in key:value pairs.
A dictionary is a collection which is ordered, changeable and do not allow duplicates.
In dictionary each element can be accessed by their keys, not through indexing.
If dictionary does not contain the key then the output will be 'KeyError'.

Example:

thisdict = {
  "brand": "Ford",
  "model": "Mustang",
  "year": 1964
}

student = {"name":"raja", "class":5}

print(thisdict)
print(student)

{'brand': 'Ford', 'model': 'Mustang', 'year': 1964}
{'name': 'raja', 'class': 5}

1. Finding frequency of each letter in a string

s = 'lakshmipritha'
name = list(s)
j = 0 
while j<len(name):
    key = name[j]
    count = 1
    i = j+1
    if key != '*':
        while i<len(name):
            if key == name[i]:
                name[i] = '*'
                count+=1
            i+=1
        print(key, count)
    j+=1

l 1
a 2
k 1
s 1
h 2
m 1
i 2
p 1
r 1
t 1

2. Letters appeared Only Once

s = 'lakshmipritha'
name = list(s)
j = 0 
while j<len(name):
    key = name[j]
    count = 1
    i = j+1
    if key != '*':
        while i<len(name):
            if key == name[i]:
                name[i] = '*'
                count+=1
            i+=1
    if count == 1 and key!='*':
        print(key, count)
    j+=1

l 1
k 1
s 1
m 1
p 1
r 1
t 1

3. Most frequent letter

s = 'lakshmipritha'
name = list(s)
j = 0 
while j<len(name):
    key = name[j]
    count = 1
    i = j+1
    if key != '*':
        while i<len(name):
            if key == name[i]:
                name[i] = '*'
                count+=1
            i+=1
    if count != 1 and key!='*':
        print(key, count)
    j+=1

a 2
h 2
i 2

4. First Non-repeated letter

s = 'lakshmipritha'
name = list(s)
j = 0 
while j<len(name):
    key = name[j]
    count = 1
    i = j+1
    if key != '*':
        while i<len(name):
            if key == name[i]:
                name[i] = '*'
                count+=1
            i+=1
    if count == 1 and key!='*':
        print(key, count)
        break
    j+=1

l 1

5. First repeated letter

s = 'lakshmipritha'
name = list(s)
j = 0 
while j<len(name):
    key = name[j]
    count = 1
    i = j+1
    if key != '*':
        while i<len(name):
            if key == name[i]:
                name[i] = '*'
                count+=1
            i+=1
    if count != 1 and key!='*':
        print(key, count)
        break
    j+=1

a 2

6. Last non-repeated letter

last = ' '
last_count = 0 
s = 'lakshmipritha'
name = list(s)
j = 0 
while j<len(name):
    key = name[j]
    count = 1
    i = j+1
    if key != '*':
        while i<len(name):
            if key == name[i]:
                name[i] = '*'
                count+=1
            i+=1
    if count == 1 and key!='*':
            last = key
            last_count = count
        #print(key, count)
    j+=1

print(last, last_count)

t 1

7. Last repeated letter

last = ' '
last_count = 0 
s = 'lakshmipritha'
name = list(s)
j = 0 
while j<len(name):
    key = name[j]
    count = 1
    i = j+1
    if key != '*':
        while i<len(name):
            if key == name[i]:
                name[i] = '*'
                count+=1
            i+=1
    if count != 1 and key!='*':
            last = key
            last_count = count
        #print(key, count)
    j+=1

print(last, last_count)

i 2

8. Most Frequent letter

s = 'lakshmipritha'
name = list(s)
j = 0 
last = ' '
last_count = 0 

while j<len(name):
    key = name[j]
    count = 1
    i = j+1
    if key != '*':
        while i<len(name):
            if key == name[i]:
                name[i] = '*'
                count+=1
            i+=1
    if count != 1 and key!='*':
        if count>last_count:
            last = key
            last_count = count
    j+=1

print(last, last_count)

a 2

9. Frequency of Vowels (a,e,i,o,u)

vowels = ['a','e','i','o','u']
last = ' '
last_count = 0 
s = 'lakshmipritha'
name = list(s)
j = 0 
while j<len(name):
    key = name[j]
    if key in vowels:
        count = 1
        i = j+1
        if key != '*':
            while i<len(name):
                if key == name[i]:
                    name[i] = '*'
                    count+=1
                i+=1
        if key!='*':
            print(key, count)
    j+=1

a 2
i 2