URI-1045 Solve

Triangle Types

Adapted by Neilor Tonin, URI  Brazil

Timelimit: 1

Read 3 double numbers (A, B and C) representing the sides of a triangle and arrange them in decreasing order, so that the side A is the biggest of the three sides. Next, determine the type of triangle that they can make, based on the following cases always writing an appropriate message:

• if A ≥ B + C, write the message: NAO FORMA TRIANGULO
• if A2 = B2 + C2, write the message: TRIANGULO RETANGULO
• if A2 > B2 + C2, write the message: TRIANGULO OBTUSANGULO
• if A2 < B2 + C2, write the message: TRIANGULO ACUTANGULO
• if the three sides are the same size, write the message: TRIANGULO EQUILATERO
• if only two sides are the same and the third one is different, write the message: TRIANGULO ISOSCELES

Input

The input contains three double numbers, A (0 < A) , B (0 < B) and C (0 < C).

Output

Print all the classifications of the triangle presented in the input.

Input Samples	Output Samples
7.0 5.0 7.0	TRIANGULO ACUTANGULO TRIANGULO ISOSCELES

6.0 6.0 10.0

TRIANGULO OBTUSANGULO TRIANGULO ISOSCELES

6.0 6.0 6.0

TRIANGULO ACUTANGULO TRIANGULO EQUILATERO

5.0 7.0 2.0

NAO FORMA TRIANGULO

6.0 8.0 10.0

TRIANGULO RETANGULO

Problem link: [URI 1045##link##]

Solution:

• [tab]
• C

• #include <stdio.h>
  
  int main()
  
  {
  
      double a, b, c, temp;
  
      scanf("%lf %lf %lf", &a, &b, &c);
  
      if (a < b)
  
      {
          temp = a;
          a = b;
          b = temp;
      }
  
      if (b < c)
  
      {
          temp = b;
          b = c;
          c = temp;
      }
  
      if (a < b)
      {
          temp = a;
          a = b;
          b = temp;
      }
  
      if (a >= b + c)
  
      {
          printf("NAO FORMA TRIANGULO\n");
      }
  
      else if (a * a == b * b + c * c)
  
      {
          printf("TRIANGULO RETANGULO\n");
      }
  
      else if (a * a > b * b + c * c)
  
      {
          printf("TRIANGULO OBTUSANGULO\n");
      }
  
      else if (a * a < b * b + c * c)
  
      {
          printf("TRIANGULO ACUTANGULO\n");
      }
  
       
  
      if (a == b && b == c)
  
      {
          printf("TRIANGULO EQUILATERO\n");
      }
  
      else if (a == b || b == c)
  
      {
          printf("TRIANGULO ISOSCELES\n");
      }
  
      return 0;
  
  }

• C++

• #include <iostream>
  #include <vector>
  #include <algorithm>
  using namespace std;
  
  int main()
  {
   float x;
   vector<float> v;
  
   for (int i = 0; i < 3; ++i)
   {
    cin >> x;
    v.push_back(x);
   }
  
   sort(v.begin(), v.begin() + 3);
   float a, b, c;
  
   c = v[0];
   b = v[1];
   a = v[2];
  
   if(a >= (b + c)){
    cout << "NAO FORMA TRIANGULO" << endl;
   }else{
  
    if(a*a == (b*b + c*c)){
     cout << "TRIANGULO RETANGULO" << endl;
    }else if(a*a > (b*b + c*c)){
     cout << "TRIANGULO OBTUSANGULO" << endl;
    }else{
     cout << "TRIANGULO ACUTANGULO" << endl;
    }
  
    if(a == b && b == c){
     cout << "TRIANGULO EQUILATERO" << endl;
    }
  
    if((a == b && a != c) || (b == c && b != a) || (c == a && c != b)){
     cout << "TRIANGULO ISOSCELES" << endl;
    }
   }
  
   return 0;
  }