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Find the type of triangle from the given sides

Given three integers A, B, and C which denote the sides of a triangle, the task is to check that the triangle is a right-angled, acute-angled, or obtuse-angled triangle.
Examples: 
 

Input: A = 1, B = 4, C = 3 
Output: Obtuse-angled Triangle 
Explanation: 
Triangle with the sides 1, 2 and 3 is an obtuse-angled triangle
Input: A = 2, B = 2, C = 2 
Output: Acute-angled Triangle 
Explanation: 
Triangle with the sides 2, 2, and 2 is an acute-angled triangle 
 




 


Approach: The idea is to use the facts from the cosine law to check the type of triangle using these formulae – 

It generalizes the Pythagorean Theorem, which states that for a right-angled triangle square of the hypotenuse is equal to the sum of squares of the base and height of the triangle, which is 
Similarly, It can be observed that 
For acute-angled triangle 

For Obtuse-angled triangle 

Below is the implementation of the above approach:
 



// C++ implementation to find
// the type of triangle with
// the help of the sides
 
#include <bits/stdc++.h>
using namespace std;
 
// Function to find the type of
// triangle with the help of sides
void checkTypeOfTriangle(int a,
                int b, int c){
    int sqa = pow(a, 2);
    int sqb = pow(b, 2);
    int sqc = pow(c, 2);
     
    if (sqa == sqb + sqc ||
        sqb == sqc + sqa ||
        sqc == sqa + sqb){
        cout << "Right-angled Triangle";
    }
    else if(sqa > sqc + sqb ||
            sqb > sqa + sqc ||
            sqc > sqa + sqb){
        cout << "Obtuse-angled Triangle";
    }
    else{
        cout << "Acute-angled Triangle";
    }
}
 
// Driver Code
int main()
{
    int a, b, c;
    a = 2;
    b = 2;
    c = 2;
     
    // Function Call
    checkTypeOfTriangle(a, b, c);
    return 0;
}

                    
// Java implementation to find
// the type of triangle with
// the help of the sides
import java.util.*;
 
class GFG
{
 
// Function to find the type of
// triangle with the help of sides
static void checkTypeOfTriangle(int a,
                int b, int c){
    int sqa = (int)Math.pow(a, 2);
    int sqb = (int)Math.pow(b, 2);
    int sqc = (int)Math.pow(c, 2);
     
    if (sqa == sqa + sqb ||
        sqb == sqa + sqc ||
        sqc == sqa + sqb){
        System.out.print("Right-angled Triangle");
    }
    else if(sqa > sqc + sqb ||
            sqb > sqa + sqc ||
            sqc > sqa + sqb){
        System.out.print("Obtuse-angled Triangle");
    }
    else{
        System.out.print( "Acute-angled Triangle");
    }
}
 
// Driver Code
public static void main (String []args)
{
    int a, b, c;
    a = 2;
    b = 2;
    c = 2;
     
    // Function Call
    checkTypeOfTriangle(a, b, c);
}
}
 
// This code is contributed by chitranayal

                    
# Python3 implementation to find
# the type of triangle with
# the help of the sides
 
# Function to find the type of
# triangle with the help of sides
def checkTypeOfTriangle(a,b,c):
    sqa = pow(a, 2)
    sqb = pow(b, 2)
    sqc = pow(c, 2)
 
    if (sqa == sqc + sqb or
        sqb == sqa + sqc or
        sqc == sqa + sqb):
        print("Right-angled Triangle")
 
    elif(sqa > sqc + sqb or
            sqb > sqa + sqc or
            sqc > sqa + sqb):
        print("Obtuse-angled Triangle")
 
    else:
        print("Acute-angled Triangle")
 
# Driver Code
if __name__ == '__main__':
    a = 2
    b = 2
    c = 2
 
    # Function Call
    checkTypeOfTriangle(a, b, c)
 
# This code is contributed by mohit kumar 29

                    
// C# implementation to find
// the type of triangle with
// the help of the sides
using System;
 
class GFG
{
  
// Function to find the type of
// triangle with the help of sides
static void checkTypeOfTriangle(int a,
                int b, int c){
    int sqa = (int)Math.Pow(a, 2);
    int sqb = (int)Math.Pow(b, 2);
    int sqc = (int)Math.Pow(c, 2);
      
    if (sqa == sqa + sqb ||
        sqb == sqa + sqc ||
        sqc == sqa + sqb){
        Console.Write("Right-angled Triangle");
    }
    else if(sqa > sqc + sqb ||
            sqb > sqa + sqc ||
            sqc > sqa + sqb){
        Console.Write("Obtuse-angled Triangle");
    }
    else{
        Console.Write( "Acute-angled Triangle");
    }
}
  
// Driver Code
public static void Main(String []args)
{
    int a, b, c;
    a = 2;
    b = 2;
    c = 2;
      
    // Function Call
    checkTypeOfTriangle(a, b, c);
}
}
 
// This code is contributed by 29AjayKumar

                    
<script>
 
// JavaScript implementation to find
// the type of triangle with
// the help of the sides
 
// Function to find the type of
// triangle with the help of sides
function checkTypeOfTriangle(a,b,c)
{
    let sqa = Math.floor(Math.pow(a, 2));
       let sqb = Math.floor(Math.pow(b, 2));
    let sqc = Math.floor(Math.pow(c, 2));
       
    if (sqa == sqa + sqb ||
        sqb == sqa + sqc ||
        sqc == sqa + sqb){
        document.write("Right-angled Triangle");
    }
    else if(sqa > sqc + sqb ||
            sqb > sqa + sqc ||
            sqc > sqa + sqb){
        document.write("Obtuse-angled Triangle");
    }
    else{
        document.write( "Acute-angled Triangle");
    }
}
 
// Driver Code
let a, b, c;
a = 2;
b = 2;
c = 2;
 
// Function Call
checkTypeOfTriangle(a, b, c);
 
// This code is contributed by rag2127
 
</script>

                    

Output
Acute-angled Triangle

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