We are given coordinates of a triangle. The task is to classify this triangle on the basis of sides and angle.
Examples:
Input: p1 = (3, 0), p2 = (0, 4), p3 = (4, 7) Output: Right Angle triangle and Isosceles Input: p1 = (0, 0), p2 = (1, 1), p3 = (1, 2); Output: Triangle is obtuse and Scalene
Approach:
- We can solve this problem by first calculating the side length and then classifying on comparing of side lengths. Classification by sides is simple, if all sides are equal, triangle will be equilateral, if any two sides are equal triangle will be Isosceles otherwise it will be Scalene.
- Now angle can be classified by Pythagoras theorem, if sum of square of two sides is equal to square of the third side, triangle will be right angle, if less triangle will be acute angle else it will be obtuse angle triangle.
Below is written simple code for classification of triangle:
C++
// C/C++ program to classify a given triangle #include <bits/stdc++.h> using namespace std;
struct point {
int x, y;
point() {}
point( int x, int y)
: x(x), y(y)
{
}
}; // Utility method to return square of x int square( int x)
{ return x * x;
} // Utility method to sort a, b, c; after this // method a <= b <= c void order( int & a, int & b, int & c)
{ int copy[3];
copy[0] = a;
copy[1] = b;
copy[2] = c;
sort(copy, copy + 3);
a = copy[0];
b = copy[1];
c = copy[2];
} // Utility method to return Square of distance // between two points int euclidDistSquare(point p1, point p2)
{ return square(p1.x - p2.x) + square(p1.y - p2.y);
} // Method to classify side string getSideClassification( int a, int b, int c)
{ // if all sides are equal
if (a == b && b == c)
return "Equilateral" ;
// if any two sides are equal
else if (a == b || b == c)
return "Isosceles" ;
else
return "Scalene" ;
} // Method to classify angle string getAngleClassification( int a, int b, int c)
{ // If addition of sum of square of two side
// is less, then acute
if (a + b > c)
return "acute" ;
// by pythagoras theorem
else if (a + b == c)
return "right" ;
else
return "obtuse" ;
} // Method to classify the triangle by sides and angles void classifyTriangle(point p1, point p2, point p3)
{ // Find squares of distances between points
int a = euclidDistSquare(p1, p2);
int b = euclidDistSquare(p1, p3);
int c = euclidDistSquare(p2, p3);
// Sort all squares of distances in increasing order
order(a, b, c);
cout << "Triangle is "
+ getAngleClassification(a, b, c)
+ " and "
+ getSideClassification(a, b, c)
<< endl;
} // Driver code int main()
{ point p1, p2, p3;
p1 = point(3, 0);
p2 = point(0, 4);
p3 = point(4, 7);
classifyTriangle(p1, p2, p3);
p1 = point(0, 0);
p2 = point(1, 1);
p3 = point(1, 2);
classifyTriangle(p1, p2, p3);
return 0;
} |
Java
// Java program to classify a given triangle import java.util.*;
class GFG
{ static class point
{ int x, y;
point() {}
public point( int x, int y)
{
this .x = x;
this .y = y;
}
}; // Utility method to return square of x static int square( int x)
{ return x * x;
} static int a, b, c;
// Utility method to sort a, b, c; after this // method a <= b <= c static void order()
{ int []copy = new int [ 3 ];
copy[ 0 ] = a;
copy[ 1 ] = b;
copy[ 2 ] = c;
Arrays.sort(copy);
a = copy[ 0 ];
b = copy[ 1 ];
c = copy[ 2 ];
} // Utility method to return Square of distance // between two points static int euclidDistSquare(point p1, point p2)
{ return square(p1.x - p2.x) + square(p1.y - p2.y);
} // Method to classify side static String getSideClassification( int a,
int b, int c)
{ // if all sides are equal
if (a == b && b == c)
return "Equilateral" ;
// if any two sides are equal
else if (a == b || b == c)
return "Isosceles" ;
else
return "Scalene" ;
} // Method to classify angle static String getAngleClassification( int a,
int b, int c)
{ // If addition of sum of square of two side
// is less, then acute
if (a + b > c)
return "acute" ;
// by pythagoras theorem
else if (a + b == c)
return "right" ;
else
return "obtuse" ;
} // Method to classify the triangle // by sides and angles static void classifyTriangle(point p1,
point p2, point p3)
{ // Find squares of distances between points
a = euclidDistSquare(p1, p2);
b = euclidDistSquare(p1, p3);
c = euclidDistSquare(p2, p3);
// Sort all squares of distances in increasing order
order();
System.out.println( "Triangle is "
+ getAngleClassification(a, b, c)
+ " and "
+ getSideClassification(a, b, c));
} // Driver code public static void main(String[] args)
{ point p1, p2, p3;
p1 = new point( 3 , 0 );
p2 = new point( 0 , 4 );
p3 = new point( 4 , 7 );
classifyTriangle(p1, p2, p3);
p1 = new point( 0 , 0 );
p2 = new point( 1 , 1 );
p3 = new point( 1 , 2 );
classifyTriangle(p1, p2, p3);
} } // This code is contributed by Rajput-Ji |
Python3
# Python program to classify a given triangle class point:
def __init__( self , x, y):
self .x = x
self .y = y
# Utility method to return square of x def square(x):
return x * x
# Utility method to sort a, b, c; after this # method a <= b <= c def order(a, b, c):
copy = [a, b, c]
copy.sort()
return copy[ 0 ], copy[ 1 ], copy[ 2 ]
# Utility method to return Square of distance # between two points def euclidDistSquare(p1, p2):
return square(p1.x - p2.x) + square(p1.y - p2.y)
# Method to classify side def getSideClassification(a, b, c):
# if all sides are equal
if a = = b and b = = c:
return "Equilateral"
# if any two sides are equal
elif a = = b or b = = c:
return "Isosceles"
else :
return "Scalene"
# Method to classify angle def getAngleClassification(a, b, c):
# If addition of sum of square of two side
# is less, then acute
if a + b > c:
return "acute"
# by pythagoras theorem
elif a + b = = c:
return "right"
else :
return "obtuse"
# Method to classify the triangle by sides and angles def classifyTriangle(p1, p2, p3):
# Find squares of distances between points
a = euclidDistSquare(p1, p2)
b = euclidDistSquare(p1, p3)
c = euclidDistSquare(p2, p3)
# Sort all squares of distances in increasing order
a, b, c = order(a, b, c)
print ( "Triangle is " , getAngleClassification(a, b, c),
" and " , getSideClassification(a, b, c))
# Driver code p1 = point( 3 , 0 )
p2 = point( 0 , 4 )
p3 = point( 4 , 7 )
classifyTriangle(p1, p2, p3) p1 = point( 0 , 0 )
p2 = point( 1 , 1 )
p3 = point( 1 , 2 )
classifyTriangle(p1, p2, p3) # The code is contributed by Gautam goel (gautamgoel962) |
C#
// C# program to classify a given triangle using System;
class GFG
{ public class point
{ public int x, y;
public point() {}
public point( int x, int y)
{
this .x = x;
this .y = y;
}
}; // Utility method to return square of x static int square( int x)
{ return x * x;
} static int a, b, c;
// Utility method to sort a, b, c; // after this method a <= b <= c static void order()
{ int []copy = new int [3];
copy[0] = a;
copy[1] = b;
copy[2] = c;
Array.Sort(copy);
a = copy[0];
b = copy[1];
c = copy[2];
} // Utility method to return // Square of distance between two points static int euclidDistSquare(point p1,
point p2)
{ return square(p1.x - p2.x) +
square(p1.y - p2.y);
} // Method to classify side static String getSideClassification( int a,
int b, int c)
{ // if all sides are equal
if (a == b && b == c)
return "Equilateral" ;
// if any two sides are equal
else if (a == b || b == c)
return "Isosceles" ;
else
return "Scalene" ;
} // Method to classify angle static String getAngleClassification( int a,
int b, int c)
{ // If addition of sum of square of
// two side is less, then acute
if (a + b > c)
return "acute" ;
// by pythagoras theorem
else if (a + b == c)
return "right" ;
else
return "obtuse" ;
} // Method to classify the triangle // by sides and angles static void classifyTriangle(point p1,
point p2,
point p3)
{ // Find squares of distances between points
a = euclidDistSquare(p1, p2);
b = euclidDistSquare(p1, p3);
c = euclidDistSquare(p2, p3);
// Sort all squares of distances
// in increasing order
order();
Console.WriteLine( "Triangle is "
+ getAngleClassification(a, b, c)
+ " and "
+ getSideClassification(a, b, c));
} // Driver code public static void Main(String[] args)
{ point p1, p2, p3;
p1 = new point(3, 0);
p2 = new point(0, 4);
p3 = new point(4, 7);
classifyTriangle(p1, p2, p3);
p1 = new point(0, 0);
p2 = new point(1, 1);
p3 = new point(1, 2);
classifyTriangle(p1, p2, p3);
} } // This code is contributed by 29AjayKumar |
Javascript
<script> // Javascript program to classify a given triangle class point { constructor(x,y)
{
this .x = x;
this .y = y;
}
} // Utility method to return square of x function square(x)
{ return x * x;
} let a, b, c; // Utility method to sort a, b, c; after this // method a <= b <= c function order()
{ let copy = new Array(3);
copy[0] = a;
copy[1] = b;
copy[2] = c;
(copy).sort( function (a,b){ return a-b;});
a = copy[0];
b = copy[1];
c = copy[2];
} // Utility method to return Square of distance // between two points function euclidDistSquare(p1,p2)
{ return square(p1.x - p2.x) + square(p1.y - p2.y);
} // Method to classify side function getSideClassification(a,b,c)
{ // if all sides are equal
if (a == b && b == c)
return "Equilateral" ;
// if any two sides are equal
else if (a == b || b == c)
return "Isosceles" ;
else
return "Scalene" ;
} // Method to classify angle function getAngleClassification(a, b, c)
{ // If addition of sum of square of two side
// is less, then acute
if (a + b > c)
return "acute" ;
// by pythagoras theorem
else if (a + b == c)
return "right" ;
else
return "obtuse" ;
} // Method to classify the triangle // by sides and angles function classifyTriangle(p1, p2, p3)
{ // Find squares of distances between points
a = euclidDistSquare(p1, p2);
b = euclidDistSquare(p1, p3);
c = euclidDistSquare(p2, p3);
// Sort all squares of distances in increasing order
order();
document.write( "Triangle is "
+ getAngleClassification(a, b, c)
+ " and "
+ getSideClassification(a, b, c)+ "<br>" );
} // Driver code let p1, p2, p3; p1 = new point(3, 0);
p2 = new point(0, 4);
p3 = new point(4, 7);
classifyTriangle(p1, p2, p3); p1 = new point(0, 0);
p2 = new point(1, 1);
p3 = new point(1, 2);
classifyTriangle(p1, p2, p3); // This code is contributed by rag2127 </script> |
Output:
Triangle is right and Isosceles Triangle is obtuse and Scalene
Time complexity : O(1)
Auxiliary Space : O(1)