c++作业4

一.分数的累加

#include <iostream>using namespace std;int main (){    double sum=0,x=0;int i=1,k=1;    while(i<=19)    {      x=i*1.0/(i+2)*k;      k=-k;      sum+=x;      i=i+2;    }    cout<<"sum="<<sum<<endl;    return 0;}

二.乘法口诀表

#include<iostream>using namespace std;int main(){    int i,j;    for(i=1;i<=6;i=i+1)    {        for(j=1;j<=i;j=j+1)        {            cout<<j<<"x"<<i<<"="<<i*j<<" ";        }        cout<<endl;    }    return 0;}

三.百钱百鸡

#include<iostream>using namespace std;int main(){    int a,b;    double c;    for (a=0;a<=20;a++)    for (b=0;b<=33;b++)    for (c=0;c<100;c++)    if (5*a+3*b+c/3==100 && a+b+c==100)        {            cout<<"鸡翁"<<a<<"只，  "<<"鸡母"<<b<<"只，  "<<"鸡雏"<<c<<"只；  "<<endl;        }     return 0;}