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

Check if Three Sides Form a Valid Triangle

Take three sides and check if they form a valid triangle.

Logic BuildingIntermediate
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:
    print("Valid triangle")
else:
    print("Invalid triangle")

Output

Enter side 1: 3
Enter side 2: 4
Enter side 3: 5
Valid triangle

Enter side 1: 1
Enter side 2: 2
Enter side 3: 5
Invalid triangle

Triangle inequality theorem: Sum of any two sides must be greater than the third side.

Key Concepts:

  • Check all three combinations: a+b>c, b+c>a, c+a>b
  • Use and to ensure all conditions are met
  • All three conditions must be True for a valid triangle
Next
Determine Triangle Type