第七週

例一：

#include<iostream>
using namespace std;

void display()
{
	cout<<"this is an example."<<endl;
}

int main()
{
	display();
	return 0;
}

例二：

#include<iostream>
using namespace std;

double min(double x,double y)
{
	return x<y?x:y;
}
int main()
{
	cout<<min(6.0,5.0)<<endl;
	return 0;
}

例三：

#include<iostream>
using namespace std;

double circleArea(double);
int main()
{
	double area = circleArea(5.0);
	cout<<"area = "<<area<<endl;
	return 0;
}
double circleArea(double r)
{
	double pi=3.14;
	double area=pi*r*r;
	return area;

}

例四：

#include<iostream>
using namespace std;

int sum(int x, int y)
{
	int temp;
	temp=x+y;
	return temp;
}
int main()
{
	int a,b,c;
	a=10;b=5;
	c=sum(a,b);
	cout<<a<<" + "<<b<<" = "<<c<<endl;
	return 0;
}

例五：

#include<iostream>
using namespace std;

int sum(int x, int y)
{
	int temp;
	temp=x+y;
	return temp;
}
int main()
{
	int a,b,c;
	a=10;b=5;
	c=sum(a,b);
	cout<<a<<" + "<<b<<" = "<<c<<endl;
	return 0;
}

例六：

#include<iostream>
using namespace std;

int max(int u, int v)
{
	int w;
	w=u>v?u:v;
	return w;
}

int main()
{
	int a,b,c;
	cout<<"please input two number: ";
	cin>>a>>b;
	c = max(a,b);
	cout<<"a="<<a<<" b= "<<b<<endl;
	cout<<"Max is "<<c<<endl;

	return 0;
}

例七：

#include<iostream>
using namespace std;

int sqr(int x)
{
	x = x*x;
	return x;
}

int main()
{
	int t=10;
	int s=sqr(t);
	cout<<"t = "<<t<<'\t'
		<<"sqr("<<t<<") = "<<s<<endl;

	return 0;
}

例八：

#include<iostream>
using namespace std;

void swap(int u,int v);

int main()
{
	int a=3;
	int b=4;
	cout<<"a = "<<a<<"\tb = "<<b<<endl;
	swap(a,b);
	cout<<"a = "<<a<<"\tb = "<<b<<endl;

	return 0;
}
void swap(int u,int v)
{
	int temp;
	temp = u;
	u=v;
	v=temp;
}

例九：

#include<iostream>
using namespace std;

void swap(int &u,int &v);

int main()
{
	int a=3;
	int b=4;
	cout<<"a = "<<a<<"\tb = "<<b<<endl;
	swap(a,b);
	cout<<"a = "<<a<<"\tb = "<<b<<endl;

	return 0;
}

void swap(int &u,int &v)
{
	int temp=v;
	v=u;
	u=temp;
}

例十：

#include<iostream>
using namespace std;

void display(int x,float y)
{
	cout<<x<<" "<<y;
	return;
}

int main()
{
	float a;
	int b;
	cin>>b>>a;
	display(b,a);

	return 0;
}

例13：

#include<iostream>
using namespace std;

long f2(int);

long f1(int p)
{
	int k;
	long r;
	k=p*p;
	r=f2(k);
	return r;
}

long f2(int q)
{
	long fact = 1;
	for(int i = 1;i<=q;i++)
		fact*=i;
	return fact;
}

int main()
{
	int i;
	long sum = 0;
	for(i=2;i<=3;i++)
		sum+=f1(i);
	cout<<"sum = "<<sum<<endl;
	return 0;
}