/*PROGRAMMER: David A. ChapmanFILE: arcLength.cppPURPOSE: Calculate the arc length of a circle based the angle and radius.FORMULA: arc length equals two times pi by the radius multiplied by the central angle (in degrees) over three hundred and sixty.*//* include directives */#include <iostream>#include <stdio.h>/* name scope */using namespace std;/* calculate_arc_length() function prototype */double calculate_arc_length(double& angle, double& radius);/* calculate_arc_length() function definition */double calculate_arc_length(double& angle, double& radius){ return 2 * 3.142 * radius * (angle / 360);}/* main() function */int main(void){ /* variables will be defined by user input */ double angle, radius; char again; /* promp the user of the program's purpose */ cout << "This program calculates the arc length of a circle." << endl << "The input for the central angle should be in degrees.\n" << endl; /* loop the input and output for multiple calculations */ do { /* prompt the user for in central angle */ cout << "Enter the central angle in degrees." << endl; cout << ":> "; cin >> angle; /* prompt the user for the radius length */ cout << "Now enter the the length of the radius." << endl; cout << ":> "; cin >> radius; /* call calculate_arc_length() to output the arc length to the user */ cout << "The arc length is " << calculate_arc_length(angle, radius) << endl; /* ask user if they need to do more calculations */ cout << "Do another calculation? (Y/N): "; cin >> again; } while(again == 'Y' || again == 'y'); /* prompt the user to press enter so that the program can close */ cout << "\nPress [ENTER] to close this window..."; getchar(); return 0;}