c++第四次上机作业

项目一、利用循环求和

#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;}

项目三、乘法口诀表

#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;}

项目七、穷举法解决问题

#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;}