Write a C program to classify a given triangle as equilateral, isosceles or scalene

classify_triangle.c

/* Write a C program to classify a given triangle as equilateral, isosceles or scalene */

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#include<stdio.h>
#include<math.h>

int main() {
  int a, b, c;
  float s, area;
 
  printf("Enter the values of the sides of the triangle: \n");
  scanf("%d %d %d", &a, &b, &c);
  if ((a + b > c && a + c > b && b + c > a) && (a > 0 && b > 0 && c > 0)) {
    s = (a + b + c) / 2.0;
    area = sqrt((s * (s - a) * (s - b) * (s - c)));
    if (a == b && b == c) {
      printf("Equilateral Triangle. \n");
      printf("Area of Equilateral Triangle is: %f", area);
    }
    else if (a == b || b == c || a == c) {
      printf("Isosceles Triangle. \n");
      printf("Area of an Isosceles Triangle: %f", area);
    }
    else {
      printf("Scalene Triangle. \n");
      printf("Area of Scalene Triangle: %f", area);
    }
  }
  else {
    printf("Triangle formation not possible");
  }

  return 0;
}