Program to find the Type of Triangle from the given Coordinates

20 Jun, 2022
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++
Java
Python3
C#
Javascript
// 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 xint square(int x){    return x * x;} // Utility method to sort a, b, c; after this// method a <= b <= cvoid 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 pointsint euclidDistSquare(point p1, point p2){    return square(p1.x - p2.x) + square(p1.y - p2.y);} // Method to classify sidestring 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 anglestring 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 anglesvoid 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 codeint 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 program to classify a given triangleimport 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 xstatic int square(int x){    return x * x;}static int a, b, c; // Utility method to sort a, b, c; after this// method a <= b <= cstatic 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 pointsstatic int euclidDistSquare(point p1, point p2){    return square(p1.x - p2.x) + square(p1.y - p2.y);} // Method to classify sidestatic 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 anglestatic 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 anglesstatic 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 codepublic 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
# Python program to classify a given triangleclass point:    def __init__(self, x, y):        self.x = x        self.y = y # Utility method to return square of xdef square(x):    return x * x # Utility method to sort a, b, c; after this# method a <= b <= cdef 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 pointsdef euclidDistSquare(p1, p2):    return square(p1.x - p2.x) + square(p1.y - p2.y) #  Method to classify sidedef 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 angledef 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 anglesdef 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 codep1 = 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# program to classify a given triangleusing 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 xstatic int square(int x){    return x * x;}static int a, b, c; // Utility method to sort a, b, c;// after this method a <= b <= cstatic 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 pointsstatic int euclidDistSquare(point p1,                            point p2){    return square(p1.x - p2.x) +           square(p1.y - p2.y);} // Method to classify sidestatic 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 anglestatic 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 anglesstatic 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 codepublic 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
<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 xfunction square(x){    return x * x;}let a, b, c; // Utility method to sort a, b, c; after this// method a <= b <= cfunction 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 pointsfunction euclidDistSquare(p1,p2){    return square(p1.x - p2.x) + square(p1.y - p2.y);} // Method to classify sidefunction 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 anglefunction 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 anglesfunction 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 codelet 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>
Triangle is right and Isosceles
Triangle is obtuse and Scalene
 
Time complexity : O(1)
Auxiliary Space : O(1)
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Rajput-Ji
29AjayKumar
rag2127
gautamgoel962
mailaruyashaswi
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Geometric
Geometric
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