Python Challenges: Encode a string amount into integer

Python Challenges - 1: Exercise-50 with Solution

Write a Python program that takes a string and encode it that the amount of symbols would be represented by integer and the symbol.
For example, the string "AAAABBBCCDAAA" would be encoded as "4A3B2C1D3A"

Sample Solution:

Python Code:

def encode_string(str1):
    encoded = ""
    ctr = 1
    last_char = str1[0]

    for i in range(1, len(str1)):

        if last_char == str1[i]:
            ctr += 1
         
        else:
            encoded += str(ctr) + last_char
            ctr = 0
            last_char = str1[i]
            ctr += 1
    encoded += str(ctr) + last_char
    return encoded
print(encode_string("AAAABBBCCDAAA")) 
print(encode_string("PHP"))  
print(encode_string("AAAABBBCCCDAABDAAAAC"))

Sample Output:

4A3B2C1D3A
1P1H1P
4A3B3C1D2A1B1D4A1C

Flowchart:

Python Code Editor:

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