c++第四次上机作业

#include <iostream.h>
void main( )
{
int i(0),sum(0);
while (i<=1000)
{
sum+=i;
i=i+2;
}
cout<<"sum="<<sum<<endl;
}

#include <iostream.h>
void main( )
{
int i(0),sum(0);
do
{
sum+=i;
i=i+2;
}while (i<=1000);
cout<<"sum="<<sum<<endl;
}

#include <iostream.h>
void main( )
{
int i,sum;
sum=0;
for(i=0;i<=1000;i=i+2)
sum=sum+i;
cout<<"sum="<<sum<<endl;
}

#include <iostream>
using namespace std;
int main( )
{
for(int i=1;i<=9;i++)
{
for(int j=1;j<=i;j++)
cout<<j<<"x"<<i<<"="<<j*i<<" ";
cout<<endl;
}
return 0;
}

#include <iostream>
using namespace std;
int main()
{
int x,y,z,count=0;
cout<<"百钱买百鸡的方案有："<<endl;
for(x=0;x<20;x++)
for(y=0;y<33;y++)
for(z=0;z<300;z++)
if(5*x+3*y+z/3==100&&x+y+z==100)
{
++count;
cout<<count<<":"<<x<<","<<y<<","<<z<<endl;
}
return 0;
}