# C program to find area of a triangle

C program to find area of a triangle: C programming code to calculate area of a triangle using Heron's or Hero's formula. User will enter the lengths of sides of the triangle. Remember for a triangle to exist the sum of any two sides of a triangle must be greater than the third side.

## C programming code

1. /* Assuming triangle exists - valid input from user */
2.
3. #include<stdio.h>
4. #include<math.h>
5.
6. int main()
7. {
8.    double a, b, c, s, area;
9.
10.    printf("Enter the sides of triangle\n");
11.
12.    scanf("%lf%lf%lf", &a, &b, &c);
13.
14.    s = (a+b+c)/2;
15.
16.    area = sqrt(s*(s-a)*(s-b)*(s-c));
17.
18.    printf("Area of the triangle = %.2lf\n", area);
19.
20.    return 0;
21. }

## C program to find area of a triangle using a function

1. #include<stdio.h>
2. #include<math.h>
3.
4. double area_of_triangle(double, double, double);
5.
6. int main()
7. {
8.    double a, b, c, area;
9.
10.    printf("Enter the lengths of sides of a triangle\n");
11.
12.    scanf("%lf%lf%lf", &a, &b, &c);
13.
14.    area = area_of_triangle(a, b, c);
15.
16.    printf("Area of the triangle = %.2lf\n", area);
17.
18.    return 0;
19. }
20.
21. double area_of_triangle(double a, double b, double c)
22. {
23.    double s, area;
24.
25.    s = (a+b+c)/2;
26.
27.    area = sqrt(s*(s-a)*(s-b)*(s-c));
28.
29.    return area;
30. }