Logic Building/Phase 1 - Level 2: Nested If & Multiple Conditions/Program

Determine Triangle Type

If sides form a valid triangle, determine if it is equilateral, isosceles, or scalene.

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Logic Building

# Take three sides as input
a = float(input("Enter side 1: "))
b = float(input("Enter side 2: "))
c = float(input("Enter side 3: "))

# Check if valid triangle
if a + b > c and b + c > a and c + a > b:
    # Valid triangle - determine type
    if a == b == c:
        print("Equilateral")
    elif a == b or b == c or c == a:
        print("Isosceles")
    else:
        print("Scalene")
else:
    print("Invalid triangle")

Output

Enter side 1: 5
Enter side 2: 5
Enter side 3: 5
Equilateral

Enter side 1: 5
Enter side 2: 5
Enter side 3: 6
Isosceles

After validating triangle, check side equality.

Key Concepts:

Equilateral: all sides equal (a == b == c)
Isosceles: two sides equal (a==b or b==c or c==a)
Scalene: all sides different
Use nested if-elif-else structure

Check if Three Sides Form a Valid Triangle

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