# Check whether triangle is valid or not if sides are given

• Difficulty Level : Basic
• Last Updated : 07 Nov, 2021

Given three sides, check whether triangle is valid or not.
Examples:

```Input :  a = 7, b = 10, c = 5
Output : Valid

Input : a = 1 b = 10 c = 12
Output : Invalid```

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Approach: A triangle is valid if sum of its two sides is greater than the third side. If three sides are a, b and c, then three conditions should be met.

```1.a + b > c
2.a + c > b
3.b + c > a  ``` ## C++

 `// C++ program to check if three``// sides form a triangle or not``#include``using` `namespace` `std;`` ` `// function to check if three sider``// form a triangle or not``bool` `checkValidity(``int` `a, ``int` `b, ``int` `c)``{``    ``// check condition``    ``if` `(a + b <= c || a + c <= b || b + c <= a)``        ``return` `false``;``    ``else``        ``return` `true``;``}`` ` `// Driver function``int` `main()``{``    ``int` `a = 7, b = 10, c = 5;``     ` `    ``if` `(checkValidity(a, b, c))``        ``cout << ``"Valid"``;``    ``else``        ``cout << ``"Invalid"``;    ``}`

## Java

 `// Java program to check ``// validity of any triangle`` ` `public` `class` `GFG {`` ` ` ` `    ``// Function to calculate for validity``    ``public` `static` `int` `checkValidity(``int` `a,``                                ``int` `b, ``int` `c)``    ``{``        ``// check condition``        ``if` `(a + b <= c || a + c <= b || b + c <= a)``            ``return` `0``;``        ``else``            ``return` `1``;``    ``}`` ` `    ``// Driver function``    ``public` `static` `void` `main(String args[])``    ``{`` ` `        ``int` `a = ``7``, b = ``10``, c = ``5``;``     ` `        ``// function calling and print output``        ``if` `((checkValidity(a, b, c)) == ``1``)``            ``System.out.print(``"Valid"``);``        ``else``            ``System.out.print(``"Invalid"``);``         ` `    ``}``}`` ` `// This article is contributed by 'Akansh Gupta'`

## Python3

 `# Python3 program to check if three``# sides form a  triangle or not `` ` `# function to check if three sides ``# form a triangle or not ``def` `checkValidity(a, b, c): ``     ` `    ``# check condition ``    ``if` `(a ``+` `b <``=` `c) ``or` `(a ``+` `c <``=` `b) ``or` `(b ``+` `c <``=` `a) :``        ``return` `False``    ``else``:``        ``return` `True`        ` ` `# driver code ``a ``=` `7``b ``=` `10``c ``=` `5``if` `checkValidity(a, b, c):``    ``print``(``"Valid"``) ``else``:``    ``print``(``"Invalid"``)`

## C#

 `// C# program to check ``// validity of any triangle``using` `System;`` ` `class` `GFG {``     ` `    ``// Function to calculate for validity``    ``public` `static` `int` `checkValidity(``int` `a, ``int` `b, ``                                    ``int` `c)``    ``{``         ` `        ``// check condition``        ``if` `(a + b <= c || a + c <= b || ``                            ``b + c <= a)``            ``return` `0;``        ``else``            ``return` `1;``    ``}`` ` `    ``// Driver code``    ``public` `static` `void` `Main()``    ``{``        ``int` `a = 7, b = 10, c = 5;``     ` `        ``// function calling and print output``        ``if` `((checkValidity(a, b, c)) == 1)``          ``Console.Write(``"Valid"``);``        ``else``          ``Console.Write(``"Invalid"``);``         ` `    ``}``}`` ` `// This code is contributed by Nitin Mittal.`

## PHP

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## Javascript

 ``

Output :

`Valid`

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