Online Learning Platform
Write a Python program to extract the numbers from a string.
"python 456 self learning 89"
[456, 89]
text = "python 456 self learning 89"print([int(w) for w in text.split() if w.isdigit()])[456, 89]
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Write a Python program to measure how similar two strings are.
"Learning is fun in Sqatools", "Sqatools Online Learning Platform"
Similarity: 0.4 Word overlap (Jaccard): 0.29
difflib.SequenceMatcher returns a ratio from 0 (different) to 1 (identical).from difflib import SequenceMatcher s1 = "Learning is fun in Sqatools"s2 = "Sqatools Online Learning Platform"ratio = SequenceMatcher(None, s1, s2).ratio()print("Similarity:", round(ratio, 2)) w1, w2 = set(s1.lower().split()), set(s2.lower().split())print("Word overlap (Jaccard):", round(len(w1 & w2) / len(w1 | w2), 2))Similarity: 0.4 Word overlap (Jaccard): 0.29
The ratio compares matching blocks of characters.
A second measure compares shared words over all distinct words.
Different similarity measures give different numbers, so state which one you use.
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Write a Python program to remove unwanted characters from a string and capitalise it.
"sqa****too^^{ls"Sqatools
capitalize().text = "sqa****too^^{ls"print("".join(ch for ch in text if ch.isalpha()).capitalize())Sqatools
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Write a Python program to count the non-empty substrings of a string.
"sqatools12"
55 55
text = "sqatools12"n = len(text)print(n * (n + 1) // 2)print(sum(1 for i in range(n) for j in range(i + 1, n + 1)))55 55
The formula counts every pair of start and end positions.
The nested loops count them one by one and confirm the formula.
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Write a Python program to count the uppercase, lowercase, special and numeric characters in a string.
"@SqaTools.lin"
Special characters: 2 Uppercase characters: 2 Lowercase characters: 9 Numeric values: 0
text = "@SqaTools.lin"upper = lower = digits = special = 0for ch in text: if ch.isupper(): upper += 1 elif ch.islower(): lower += 1 elif ch.isdigit(): digits += 1 else: special += 1print("Special characters:", special)print("Uppercase characters:", upper)print("Lowercase characters:", lower)print("Numeric values:", digits)Special characters: 2 Uppercase characters: 2 Lowercase characters: 9 Numeric values: 0
“@SqaTools.lin” has 2 special characters (@ and .) and 9 lowercase letters; the original sample showed 1 and 8.
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Write a Python program to remove all characters except a given one.
"Sqatools python", keep "S"
S
text = "Sqatools python"keep = "S"print("".join(ch for ch in text if ch == keep))S
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Write a Python program to build a string from the characters that appear in only one of two strings.
"abcdefg", "xyzabcd"
efgxyz
s1, s2 = "abcdefg", "xyzabcd"result = [ch for ch in s1 if ch not in s2] + [ch for ch in s2 if ch not in s1]print("".join(result))efgxyz
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Write a Python program to build a string of the characters that occur more than once.
"aabbcceffgh"
abcf
from collections import Countertext = "aabbcceffgh"counts = Counter(text)print("".join(ch for ch in counts if counts[ch] > 1))abcf
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Write a Python program to collapse consecutive duplicate characters into one.
"xxxxyy"
xyx
text = "xxxxyyxx"result = ""for ch in text: if not result or ch != result[-1]: result += chprint(result)xyx
not result handles the first character.
Only consecutive repeats are removed, so “xxxxyyxx” becomes “xyx”.
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Write a Python program to find the longest run of consecutive 0s in a binary string.
"10001100000111"
5
binary = "10001100000111"print(max(len(run) for run in binary.split("1")))5
Splitting on “1” leaves only the runs of zeros.
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