formula to verify if it is a triangle
Formula : any of 2 side is must be bigger than the third side.
suppose, x = side1, y = side2, z = side3 of a triangle.
here are the steps to check that if it's a triangle. If all the condition become
true than it's a triangle otherwise not.
1. x + y > z.
2. x + z > y.
3. z + y > x.