Geometric Formulas

• Circle: Area = π × r²
• Rectangle: Area = length × width
• Triangle (Heron's Formula): Area = √(s(s - a)(s - b)(s - c)) where s = (a + b + c) / 2
• Sphere Surface Area: Area = 4 × π × r²

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Complete C Implementation

c (ISO Standard)
Run in Compiler.cCopy
#include <stdio.h>
#include <math.h>

#define PI 3.14159265358979323846

double areaCircle(double radius) {
    return PI * radius * radius;
}

double areaRectangle(double length, double width) {
    return length * width;
}

double areaTriangle(double a, double b, double c) {
    double s = (a + b + c) / 2.0;
    return sqrt(s * (s - a) * (s - b) * (s - c));
}

int main() {
    double r = 5.0;
    double l = 10.0, w = 4.0;
    double a = 3.0, b = 4.0, c = 5.0;

    printf("Geometric Shape Area Computations in C:\n\n");
    printf("  Circle (r = %.1f):        Area = %.2f\n", r, areaCircle(r));
    printf("  Rectangle (%.1f x %.1f):  Area = %.2f\n", l, w, areaRectangle(l, w));
    printf("  Triangle (%.1f,%.1f,%.1f): Area = %.2f\n", a, b, c, areaTriangle(a, b, c));

    return 0;
}

Sample Output

text (ISO Standard)
Copy
Geometric Shape Area Computations in C:

  Circle (r = 5.0):        Area = 78.54
  Rectangle (10.0 x 4.0):  Area = 40.00
  Triangle (3.0,4.0,5.0): Area = 6.00

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Complexity Analysis

• Time Complexity: O(1) constant time evaluation.
• Space Complexity: O(1) stack variables.

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Related Programs

• Unit conversions in Temperature Conversion in C.
• Basic arithmetic in Simple Calculator in C.