循环结构程序设计

输入实数x和整数n,输出x+x^2+…+xn

#include <iostream>
#include <cmath>

using namespace std;

int main()
{
	double x,sum=0;
	int n;

	cout<<"pls input x and n:";
	cin>>x>>n;

	for(int i=1;i<=n;i++)
	{
		sum+=pow(x,i);
	}
	
	cout<<"sum="<<sum<<endl;

	return 0;
}

#include <iostream>
#include <cmath>

using namespace std;

int main()
{
	double sum=0;
	int m,n;
	
	cout<<"pls input m and n:";
	cin>>m>>n;

	for(int i=1;i<=2*m-1;i+=2)
	{
		sum+=pow(i,n);
	}
	
	cout<<"sum="<<sum<<endl;

	return 0;
}

#include <iostream>
#include <cmath>
using namespace std;    
int main()
{
	int f1=1,f2=1,f3;
	
	cout<<f1<<"\t"<<f2;
	for(int i=3;i<=20;i++)
	{
		f3 = f1 + f2;
		cout<<"\t"<<f3;
		f1 = f2;
		f2 = f3;
	}

    return 0;
}

   #include <iostream>
    #include <cmath>
    using namespace std;    
    int main()
    {
        for(int i=100;i<=999;i++)
        {
            int a,b,c;
            a=i/100;
            b=(i-bai*100)/10;
            c=i%10;
            if(pow(a,3)+pow(b,3)+pow(c,3) == i)
                cout<<"找到一个水仙花数:"<<i<<endl;
        }
        return 0;
    }

#include <iostream>
using namespace std;    
int main()
{
int x,p=0,n=0,j=0,o=0;
cin>>x;
while(x!=0)
{
if(x>0)
p++;
if(x<0)
n++;
if(x%2==0)
o++;
else if(x%2!=0)
j++;
cin>>x;
}

cout<<p<<"		"<<n<<"		"<<j<<"		"<<o;
return 0;
}```