Check if a point is inside a circle

From CodeChef. Point-in-circle test via distance vs radius. Solve the geometry problem "Check if a point is inside a circle".

Examples
Input: [1,2,3]
Output: 0
Hints

Check if a point is inside a circle

**From CodeChef.** Point-in-circle test via distance vs radius. Solve the geometry problem "Check if a point is inside a circle".