- Write a C program to check whether input triangle is equilateral, isosceles or scalene triangle using if else statement.

#### Required Knowledge

- A triangle is
**equilateral triangle**, If it's sides are equal. - A triangle is
**isosceles triangle**, If any two sides of a triangle are equal. - A triangle is
**scalene triangle**, If none of the sides are equal.

## C program to check whether input triangle is equilateral, isosceles or scalene triangle

/* * Write a C program to check whether a Triangle is Equilateral, * Scalene or Isosceles */ #include <stdio.h> int main() { int side1, side2, side3; /* * Take length of three sides of triangle as input * from user using scanf */ printf("Enter Length of Three Sides of a Triangle\n"); scanf("%d %d %d", &side1, &side2, &side3); if((side1 == side2)&&(side2 == side3)) { /* All Sides Equal, Hence Equilateral */ printf("It is an Equilateral Triangle\n"); } else if (side1!=side2 && side2!=side3 && side3!=side1) { /* All sides different, Hence Scelene */ printf("It is a Scalene Triangle\n"); } else { /* Two sides equal, Hence Isoscales */ printf("It is an Isoscales Triangle\n"); } return 0; }

Output

Enter Length of Three Sides of a Triangle 10 10 10 It is an Equilateral Triangle

Enter Length of Three Sides of a Triangle 10 10 5 It is an Isoscales Triangle

Enter Length of Three Sides of a Triangle 7 10 5 It is an Isoscales Triangle

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