This page is still under construction.

Parts of this page are still being built. What you see may change.

Triangle and Its Three Sides

Interview

Time limit1sMemory limit128 MB

Summary
Read triples of positive integers until 0 0 0, and for each print Equilateral, Isosceles, Scalene, or Invalid based on equal sides and the triangle inequality.
Level

Easy1 of 10

Topics
Implementation, Math, Sorting
Solved
No attempts yet

Problem

Given the lengths of the three sides of a triangle, classify it according to the following definitions.

  • Equilateral: all three sides have the same length
  • Isosceles: exactly two sides have the same length
  • Scalene: all three sides have different lengths

However, if the three given lengths cannot form a triangle, output "Invalid". The lengths cannot form a triangle when the sum of the two shorter sides is not greater than the longest side (that is, less than or equal to it). For example, 6, 3, 2 is such a case, since the longest side 6 is greater than 3 + 2 = 5.

Given the three side lengths, print the result according to the definitions above.

Input

Each line contains three positive integers, each not exceeding 1,000, separated by spaces. The last line is 0 0 0; this line marks the end of the input and is not processed.

Output

For each input line, print the corresponding result (Equilateral, Isosceles, Scalene, or Invalid), one per line.

Examples1

  1. Example 1

    Input
    7 7 7
6 5 4
3 2 5
6 2 6
0 0 0
    Expected output
    Equilateral
Scalene
Invalid
Isosceles