तीन Numbers में सबसे बड़ा — code, output और dry run

Problem statement

Approach 1: simple loop

Compare with an if/elif ladder. Each condition asks "is this number at least as large as both others?" and the first true branch wins.

a, b, c = 12, 45, 23

if a >= b and a >= c:
    largest = a
elif b >= a and b >= c:
    largest = b
else:
    largest = c

print(largest)
# Output: 45

Note the >=: with ties like 7, 7, 3, the first branch still fires and the answer is correct.

Approach 2: reusable function

Keep a running champion: start with the first number, replace it whenever a later number beats it. This shape scales to ten numbers without changing its logic.

def largest_of(numbers):
    best = numbers[0]
    for n in numbers[1:]:
        if n > best:
            best = n
    return best

print(largest_of([12, 45, 23]))       # 45
print(largest_of([5, 5, 5]))          # 5
print(largest_of([-2, -9, -4]))       # -2

Only two ideas: remember the best so far, and update on a strict win. The negative-numbers case works because every comparison is relative.

Approach 3: Pythonic alternative

Python has a built-in for "largest": max(). It accepts any number of arguments, or a single list, and even a key function for custom ordering.

a, b, c = 12, 45, 23

print(max(a, b, c))          # 45
print(max([12, 45, 23]))     # 45 — same thing via a list

For exams, write the ladder; for code you will keep, max() says exactly what it means.

Dry run

Common errors

• or की जगह and — "or" से गलत number भी pass हो जाता है।
• = बनाम == की अदला-बदली।
• सबसे बड़ा मानकर 0 से शुरू करना — सब negative हों तो जवाब गलत; पहले number से शुरू करो।
• Ties भूलना — हर जगह strict > लिखने से ladder में जवाब set ही नहीं होता।
• तीनों branch के results print कर देना।

Practice on PyDebug

Concept समझने के बाद इन free problems को browser में solve करें:

• Range boundary practice
• Operator precedence practice
• Variables and assignment practice