02.cpp

来自「今天我有时清」· C++ 代码 · 共 11 行

#include<iostream.h>
void main()
{
	const float pai = 3.14;
	float radius;
	cout<<"Enter radius:";
	cin>>radius;
	float area=pai*radius*radius;
	cout<<"\n The area of circle is ";
	cout<<area<<endl;
}