# Calculate Area Of Circle, Rectangle,Square And Triangle using functions/subroutines/methods/procedures in C++

LEVEL: Beginner

Whats in this post?

1. Code
2. Output
3. Background and Explanation of the code

Code

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Background and Explanation of the code

This is a simple program which calculates the area of the different shapes like circle,rectangle,square and triangle by calling different functions/procedures. In this program, firstly the constant pi=3.14 and other variables are defined. Then the program calculates the area of circle. Here, two different functions have been defined for input and output. Output calculates the area of circle using the formula area=rad*rad*pie . After this, the program calls another subroutines which takes two different inputs from user – length and width and calculate the area of rectangle and square and shows it to user. The area of rectangle is calculated using the formula area=length*width. There are also three different function calls for triangle. One calculates sum and print area of triangle. The second checks whether the sum of two sides of triangle is not greater than the third side. The third function calculates the area of triangle using the sqrt function of MATH library.